<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2024 Workiva-->
<!--r:4d687a72-6e48-4a9b-8843-00cbf86073b6,g:21b84c6a-c046-491b-8946-1083c89eee31-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel"/>
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="simple" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel"/>
  <link:labelLink xlink:role="http://www.xbrl.org/2003/role/link" xlink:type="extended">
    <link:label id="lab_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_4fc4d4a9-2ba9-49e9-838c-806e9660fc8b_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Sales</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_70091e36-b97a-47d9-8f9c-2df8a11fa4d9_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from sales of AFS of securities</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_label_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Sale of Debt Securities, Available-for-Sale</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt" xlink:to="lab_us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_e9f6700a-3e81-4e7a-b571-bcf3d6647c82_verboseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net changes in operating assets and liabilities which provided (used) cash:</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_3b51a6b9-18b0-4675-8e90-f61798aeed6d_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in operating assets and liabilities which used cash</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Operating Capital [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:to="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RelatedPartyTransactionLineItems_8bbb43aa-4dc4-4c40-a19e-ce158b2ace4d_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party Transaction [Line Items]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionLineItems_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transaction [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems" xlink:to="lab_us-gaap_RelatedPartyTransactionLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward_06645b79-a9af-41f7-b6d1-b94d7f4aeff9_terseLabel_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward_label_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value [Roll Forward]</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward_documentation_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward" xlink:href="isba-20231231.xsd#isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward" xlink:to="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized_37ced522-6cad-4764-9178-2a11e21c297a_terseLabel_en-US" xlink:label="lab_us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Banking Regulation, Common Equity Tier 1 Risk-Based Capital, Well Capitalized, Minimum</link:label>
    <link:label id="lab_us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized_label_en-US" xlink:label="lab_us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Common Equity Tier 1 Risk-Based Capital, Well Capitalized, Minimum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized" xlink:to="lab_us-gaap_CommonEquityTierOneCapitalRequiredToBeWellCapitalized" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent_f11c0f9f-c470-458d-a505-7570597d8c49_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Comprehensive income (loss) before income tax (expense) benefit</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, before Tax, Portion Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:to="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentBeforeTaxPortionAttributableToParent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_88a1c5be-10e8-4698-8053-a0ec3f503655_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Award Type [Domain]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Award Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NoninterestBearingDepositLiabilities_2cdacfc4-90e7-4c01-acd2-5ed1ffad05f4_verboseLabel_en-US" xlink:label="lab_us-gaap_NoninterestBearingDepositLiabilities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Noninterest bearing</link:label>
    <link:label id="lab_us-gaap_NoninterestBearingDepositLiabilities_label_en-US" xlink:label="lab_us-gaap_NoninterestBearingDepositLiabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noninterest-Bearing Deposit Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestBearingDepositLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoninterestBearingDepositLiabilities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoninterestBearingDepositLiabilities" xlink:to="lab_us-gaap_NoninterestBearingDepositLiabilities" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium_c6d0262f-ac94-4018-88ae-6ae688ca2a04_negatedLabel_en-US" xlink:label="lab_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net amortization of AFS securities</link:label>
    <link:label id="lab_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium_4d4e2805-e875-42f8-8d4a-27c4843dd1dc_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investment Income, Net, Amortization of Discount and Premium</link:label>
    <link:label id="lab_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium_label_en-US" xlink:label="lab_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment Income, Net, Amortization of Discount and Premium</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium" xlink:to="lab_us-gaap_InvestmentIncomeNetAmortizationOfDiscountAndPremium" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock_fdc7104b-50cf-414b-adc5-3ee8677fda9e_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Amortized cost and fair value of available-for-sale securities</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Available-for-Sale Securities Reconciliation [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesReconciliationTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification_22abdad7-b4a7-4f67-b340-b537b1580e7c_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Modified, Weighted Average Interest Rate Decrease from Modification</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification" xlink:to="lab_us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestRateBelowMarketReductionMember_3c23b201-afa5-464b-9beb-c91461840a23_terseLabel_en-US" xlink:label="lab_us-gaap_InterestRateBelowMarketReductionMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Rate Below Market Reduction [Member]</link:label>
    <link:label id="lab_us-gaap_InterestRateBelowMarketReductionMember_label_en-US" xlink:label="lab_us-gaap_InterestRateBelowMarketReductionMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Rate Below Market Reduction [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateBelowMarketReductionMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestRateBelowMarketReductionMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestRateBelowMarketReductionMember" xlink:to="lab_us-gaap_InterestRateBelowMarketReductionMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue_b6846c6e-55db-4720-9404-394f1e97a8d0_verboseLabel_en-US" xlink:label="lab_isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Percent of assets and liabilities measured at fair value</link:label>
    <link:label id="lab_isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue_label_en-US" xlink:label="lab_isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Percentage of Assets and Liabilities Measured at Fair Value</link:label>
    <link:label id="lab_isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue_documentation_en-US" xlink:label="lab_isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Percent of assets and liabilities measured at fair value.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue" xlink:href="isba-20231231.xsd#isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue" xlink:to="lab_isba_PercentageOfAssetsAndLiabilitiesMeasuredAtFairValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EarningsPerShareDilutedLineItems_5bfb6fe6-9822-4826-b9ce-1dbff2e3e31c_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDilutedLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareDilutedLineItems_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareDilutedLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDilutedLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EarningsPerShareDilutedLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareDilutedLineItems" xlink:to="lab_us-gaap_EarningsPerShareDilutedLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LoansReceivableCollateralizedByLivestockMember_39098ae1-cd32-43da-93f8-0b805dd7653e_terseLabel_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByLivestockMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Livestock [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByLivestockMember_label_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByLivestockMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Livestock [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByLivestockMember_documentation_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByLivestockMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Livestock [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LoansReceivableCollateralizedByLivestockMember" xlink:href="isba-20231231.xsd#isba_LoansReceivableCollateralizedByLivestockMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LoansReceivableCollateralizedByLivestockMember" xlink:to="lab_isba_LoansReceivableCollateralizedByLivestockMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock_29bcb9ff-c5cc-4056-9b00-809006e6b8c4_terseLabel_en-US" xlink:label="lab_isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Residential Real Estate and Consumer Loan Segments by Year of Origination</link:label>
    <link:label id="lab_isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock_label_en-US" xlink:label="lab_isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Residential Real Estate and Consumer Loan Segments by Year of Origination [Table Text Block]</link:label>
    <link:label id="lab_isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock_documentation_en-US" xlink:label="lab_isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of Residential Real Estate and Consumer Loan Segments by Year of Origination</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock" xlink:href="isba-20231231.xsd#isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock" xlink:to="lab_isba_ScheduleOfResidentialRealEstateAndConsumerLoanSegmentsByYearOfOriginationTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EquipmentExpense_026c363b-d611-4528-a706-63f3aed52306_verboseLabel_en-US" xlink:label="lab_us-gaap_EquipmentExpense" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Furniture and equipment</link:label>
    <link:label id="lab_us-gaap_EquipmentExpense_label_en-US" xlink:label="lab_us-gaap_EquipmentExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equipment Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquipmentExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquipmentExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquipmentExpense" xlink:to="lab_us-gaap_EquipmentExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue_cfcd1bd0-2550-4370-acaa-f7abef3a512e_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherRealEstateAndForeclosedAssets_0295f46d-e91f-4b56-be23-1953c0539b30_terseLabel_en-US" xlink:label="lab_us-gaap_OtherRealEstateAndForeclosedAssets" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Real Estate, Foreclosed Assets, and Repossessed Assets</link:label>
    <link:label id="lab_us-gaap_OtherRealEstateAndForeclosedAssets_label_en-US" xlink:label="lab_us-gaap_OtherRealEstateAndForeclosedAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Real Estate, Foreclosed Assets, and Repossessed Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherRealEstateAndForeclosedAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherRealEstateAndForeclosedAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherRealEstateAndForeclosedAssets" xlink:to="lab_us-gaap_OtherRealEstateAndForeclosedAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_617e4a92-0cd3-4c0d-8481-53fb84c02f5a_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of Financing Receivable [Domain]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_be6a6a5f-0b3f-4087-8972-dd66c354d81b_verboseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Class of Financing Receivable [Domain]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Financing Receivable [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain" xlink:to="lab_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DisaggregationOfRevenueLineItems_846ccd57-5656-487c-afc7-0ba6eaa50519_terseLabel_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disaggregation of Revenue [Line Items]</link:label>
    <link:label id="lab_us-gaap_DisaggregationOfRevenueLineItems_label_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disaggregation of Revenue [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems" xlink:to="lab_us-gaap_DisaggregationOfRevenueLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancialAssetNotPastDueMember_3f889ca9-9bc9-476b-a8ff-4eb8c36bbcfc_terseLabel_en-US" xlink:label="lab_us-gaap_FinancialAssetNotPastDueMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Asset, Not Past Due</link:label>
    <link:label id="lab_us-gaap_FinancialAssetNotPastDueMember_label_en-US" xlink:label="lab_us-gaap_FinancialAssetNotPastDueMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Asset, Not Past Due [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetNotPastDueMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancialAssetNotPastDueMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialAssetNotPastDueMember" xlink:to="lab_us-gaap_FinancialAssetNotPastDueMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_InterestIncomeFederalFundsSoldAndOther_c7892a1c-c254-4f12-b2f7-47c00b4999e1_verboseLabel_en-US" xlink:label="lab_isba_InterestIncomeFederalFundsSoldAndOther" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Federal funds sold and other</link:label>
    <link:label id="lab_isba_InterestIncomeFederalFundsSoldAndOther_label_en-US" xlink:label="lab_isba_InterestIncomeFederalFundsSoldAndOther" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Income Federal Funds Sold and Other</link:label>
    <link:label id="lab_isba_InterestIncomeFederalFundsSoldAndOther_documentation_en-US" xlink:label="lab_isba_InterestIncomeFederalFundsSoldAndOther" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Federal funds sold and other.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_InterestIncomeFederalFundsSoldAndOther" xlink:href="isba-20231231.xsd#isba_InterestIncomeFederalFundsSoldAndOther"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_InterestIncomeFederalFundsSoldAndOther" xlink:to="lab_isba_InterestIncomeFederalFundsSoldAndOther" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubordinatedDebtMember_eb60efdf-b458-4ec6-945a-224127666420_terseLabel_en-US" xlink:label="lab_us-gaap_SubordinatedDebtMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subordinated Debt</link:label>
    <link:label id="lab_us-gaap_SubordinatedDebtMember_label_en-US" xlink:label="lab_us-gaap_SubordinatedDebtMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subordinated Debt [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubordinatedDebtMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubordinatedDebtMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubordinatedDebtMember" xlink:to="lab_us-gaap_SubordinatedDebtMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_BankOwnedLifeInsuranceIncome_d5203e3c-5bdd-45ca-a179-b32aded9e31d_verboseLabel_en-US" xlink:label="lab_us-gaap_BankOwnedLifeInsuranceIncome" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Earnings on corporate owned life insurance policies</link:label>
    <link:label id="lab_us-gaap_BankOwnedLifeInsuranceIncome_label_en-US" xlink:label="lab_us-gaap_BankOwnedLifeInsuranceIncome" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bank Owned Life Insurance Income</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankOwnedLifeInsuranceIncome" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_BankOwnedLifeInsuranceIncome"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BankOwnedLifeInsuranceIncome" xlink:to="lab_us-gaap_BankOwnedLifeInsuranceIncome" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfSubordinatedBorrowingTextBlock_9480ddea-3cc0-4d93-98f1-a125332263b6_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSubordinatedBorrowingTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Subordinated Borrowing</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSubordinatedBorrowingTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSubordinatedBorrowingTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Subordinated Borrowing [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSubordinatedBorrowingTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfSubordinatedBorrowingTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSubordinatedBorrowingTextBlock" xlink:to="lab_us-gaap_ScheduleOfSubordinatedBorrowingTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_DirectorMember_7adfc499-f8f5-4a4d-a636-67fcb42ebdcf_terseLabel_en-US" xlink:label="lab_srt_DirectorMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Director [Member]</link:label>
    <link:label id="lab_srt_DirectorMember_bbd89095-0f50-4942-806b-e387ad8b2b83_verboseLabel_en-US" xlink:label="lab_srt_DirectorMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Director [Member]</link:label>
    <link:label id="lab_srt_DirectorMember_label_en-US" xlink:label="lab_srt_DirectorMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Director [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_DirectorMember" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_DirectorMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_DirectorMember" xlink:to="lab_srt_DirectorMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_0d01e4c9-59a8-4e43-8a59-a65548137f8b_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Actuarial assumptions used</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfAssumptionsUsedTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_b5229f11-4fb1-46f7-b007-8b7b0978a2c2_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred (benefit) expense</link:label>
    <link:label id="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_label_en-US" xlink:label="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Federal Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredFederalIncomeTaxExpenseBenefit"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:to="lab_us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections_ed10f9a1-be4d-42de-a200-836c8d74dee7_negatedLabel_en-US" xlink:label="lab_isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Loan principal (originations) collections, net</link:label>
    <link:label id="lab_isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections_label_en-US" xlink:label="lab_isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments For (Proceeds From) Loan And Lease Originations And Principal Collections</link:label>
    <link:label id="lab_isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections_documentation_en-US" xlink:label="lab_isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Payments For (Proceeds From) Loan And Lease Originations And Principal Collections</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections" xlink:href="isba-20231231.xsd#isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections" xlink:to="lab_isba_PaymentsForProceedsFromLoanAndLeaseOriginationsAndPrincipalCollections" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsOfDividendsCommonStock_d7a09c85-c389-4403-b1e5-1630fa2fdc01_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsOfDividendsCommonStock" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Cash dividends paid on common stock</link:label>
    <link:label id="lab_us-gaap_PaymentsOfDividendsCommonStock_label_en-US" xlink:label="lab_us-gaap_PaymentsOfDividendsCommonStock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments of Ordinary Dividends, Common Stock</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividendsCommonStock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsOfDividendsCommonStock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsOfDividendsCommonStock" xlink:to="lab_us-gaap_PaymentsOfDividendsCommonStock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_23f42677-7e85-4052-ada1-832464033e45_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Diluted (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Diluted</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareDiluted" xlink:to="lab_us-gaap_EarningsPerShareDiluted" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTextBlock_28ac086a-a84a-4563-af42-ecf143a97e27_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Components of shares eligible to be issued under the Directors Plan</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Deferred Compensation Arrangement with Individual, Share-Based Payments [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTextBlock" xlink:to="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember_4ef5fecd-6311-4080-aeb7-0a89ab13240d_terseLabel_en-US" xlink:label="lab_isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Residential Real Estate, Home Equity Lines of Credit, Portfolio Segment</link:label>
    <link:label id="lab_isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Residential Real Estate, Home Equity Lines of Credit, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Residential Real Estate, Home Equity Lines of Credit, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember" xlink:to="lab_isba_ResidentialRealEstateHomeEquityLinesOfCreditPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForInvestmentsForeclosedAssetsPolicy_11e52b74-a953-4552-b142-961f00476359_verboseLabel_en-US" xlink:label="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForInvestmentsForeclosedAssetsPolicy" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">FORECLOSED ASSETS</link:label>
    <link:label id="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForInvestmentsForeclosedAssetsPolicy_label_en-US" xlink:label="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForInvestmentsForeclosedAssetsPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Held-for-Investment, Foreclosed Asset [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLoanAndLeaseReceivablesHeldForInvestmentsForeclosedAssetsPolicy" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinanceLoanAndLeaseReceivablesHeldForInvestmentsForeclosedAssetsPolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinanceLoanAndLeaseReceivablesHeldForInvestmentsForeclosedAssetsPolicy" xlink:to="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForInvestmentsForeclosedAssetsPolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock_ba391b48-46c8-492a-bd0c-08a0d22f4bec_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Components of net periodic benefit cost</link:label>
    <link:label id="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Net Benefit Costs [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfNetBenefitCostsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock_1dae54d6-9932-4ce6-9e11-d2e8554e058b_verboseLabel_en-US" xlink:label="lab_isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Schedule of equity method and other investments</link:label>
    <link:label id="lab_isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock_label_en-US" xlink:label="lab_isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Equity Method And Other Investments [Table Text Block]</link:label>
    <link:label id="lab_isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock_documentation_en-US" xlink:label="lab_isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of Equity Method And Other Investments [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock" xlink:href="isba-20231231.xsd#isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock" xlink:to="lab_isba_ScheduleofEquityMethodAndOtherInvestmentsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_c14cc9bd-c828-44a0-a537-8a65761f765a_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">OCI before reclassifications</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), before Reclassifications, before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsToAcquireEquityMethodInvestments_b3eb830e-28a5-43e8-97b3-5fa850c8fd55_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireEquityMethodInvestments" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Payments to Acquire Equity Method Investments</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquireEquityMethodInvestments_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireEquityMethodInvestments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Equity Method Investments</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireEquityMethodInvestments" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsToAcquireEquityMethodInvestments"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireEquityMethodInvestments" xlink:to="lab_us-gaap_PaymentsToAcquireEquityMethodInvestments" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedInCurrentFiscalYear_3eec433c-f65d-40e2-9e73-2ae89647793d_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedInCurrentFiscalYear" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year One, Originated, Current Fiscal Year</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedInCurrentFiscalYear_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedInCurrentFiscalYear" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year One, Originated, Current Fiscal Year</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableOriginatedInCurrentFiscalYear" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableOriginatedInCurrentFiscalYear"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableOriginatedInCurrentFiscalYear" xlink:to="lab_us-gaap_FinancingReceivableOriginatedInCurrentFiscalYear" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ConsumerUnsecuredPortfolioSegmentMember_63b88a8b-190c-43b7-a3c5-9c0802a5844a_terseLabel_en-US" xlink:label="lab_isba_ConsumerUnsecuredPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consumer, Unsecured, Portfolio Segment</link:label>
    <link:label id="lab_isba_ConsumerUnsecuredPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_ConsumerUnsecuredPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consumer, Unsecured, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_ConsumerUnsecuredPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_ConsumerUnsecuredPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Consumer, Unsecured, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ConsumerUnsecuredPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_ConsumerUnsecuredPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ConsumerUnsecuredPortfolioSegmentMember" xlink:to="lab_isba_ConsumerUnsecuredPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesMember_54ac2c36-8705-4446-83b1-caa1f61bbeb6_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities [Member]</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesMember_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesMember" xlink:to="lab_us-gaap_DebtSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax_4548aaa2-04c3-480c-ba68-fb13ff25c195_negatedLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Tax effect</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueDisclosuresAbstract_a7b2a849-95a9-499f-a503-c17231fdaa6e_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueDisclosuresAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Disclosures [Abstract]</link:label>
    <link:label id="lab_us-gaap_FairValueDisclosuresAbstract_label_en-US" xlink:label="lab_us-gaap_FairValueDisclosuresAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Disclosures [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosuresAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueDisclosuresAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosuresAbstract" xlink:to="lab_us-gaap_FairValueDisclosuresAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DepositsNegotiableOrderOfWithdrawalNOW_7aa0b7c0-f82a-419c-81b3-532ad3e7d758_verboseLabel_en-US" xlink:label="lab_us-gaap_DepositsNegotiableOrderOfWithdrawalNOW" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">NOW accounts</link:label>
    <link:label id="lab_us-gaap_DepositsNegotiableOrderOfWithdrawalNOW_label_en-US" xlink:label="lab_us-gaap_DepositsNegotiableOrderOfWithdrawalNOW" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deposits, Negotiable Order of Withdrawal (NOW)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsNegotiableOrderOfWithdrawalNOW" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepositsNegotiableOrderOfWithdrawalNOW"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepositsNegotiableOrderOfWithdrawalNOW" xlink:to="lab_us-gaap_DepositsNegotiableOrderOfWithdrawalNOW" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_9650af3a-a3eb-4c1d-820e-4fa0c41ae79d_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Benefits Paid</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Benefits Paid</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:to="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff_d8deaddf-8206-4486-97b6-fce08b8ad427_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff" xlink:to="lab_us-gaap_FinancingReceivableOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_2d23b3ef-9cb1-4dc5-9c56-7e82c180af70_verboseLabel_en-US" xlink:label="lab_us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">AFS Securities</link:label>
    <link:label id="lab_us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock" xlink:to="lab_us-gaap_InvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StockholdersEquityAbstract_b972f1d5-762b-436a-8aa1-beef8394b0ae_verboseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Shareholders' equity</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityAbstract_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity, Attributable to Parent [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquityAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityAbstract" xlink:to="lab_us-gaap_StockholdersEquityAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_329e8c21-0ec3-4090-a2bd-21cdf97a007b_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Line Items]</link:label>
    <link:label id="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems_label_en-US" xlink:label="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:to="lab_us-gaap_ReclassificationAdjustmentOutOfAccumulatedOtherComprehensiveIncomeLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_e8715387-7969-4976-8fba-c4ba338b9d69_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Computation of earnings per common share</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalDepositInsuranceCorporationPremiumExpense_e6489de0-8239-4691-9f9e-c48f707477da_verboseLabel_en-US" xlink:label="lab_us-gaap_FederalDepositInsuranceCorporationPremiumExpense" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">FDIC insurance premiums</link:label>
    <link:label id="lab_us-gaap_FederalDepositInsuranceCorporationPremiumExpense_label_en-US" xlink:label="lab_us-gaap_FederalDepositInsuranceCorporationPremiumExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Deposit Insurance Corporation Premium Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalDepositInsuranceCorporationPremiumExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalDepositInsuranceCorporationPremiumExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalDepositInsuranceCorporationPremiumExpense" xlink:to="lab_us-gaap_FederalDepositInsuranceCorporationPremiumExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_b9ff09bc-6e3a-4fcf-b7f1-51554b776d5b_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of Shares</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueInputsLevel1Member_a0c8afb3-d296-4f61-8412-1ccd7bbad34c_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel1Member" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Level 1 [Member]</link:label>
    <link:label id="lab_us-gaap_FairValueInputsLevel1Member_label_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel1Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Inputs, Level 1 [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel1Member" xlink:to="lab_us-gaap_FairValueInputsLevel1Member" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialAndAgriculturalPortfolioSegmentMember_a88fb7c8-0cf3-41b7-a414-27412ffcd2a9_terseLabel_en-US" xlink:label="lab_isba_CommercialAndAgriculturalPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial And Agricultural Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialAndAgriculturalPortfolioSegmentMember_33c8936f-8e91-4fb0-9755-8a8efb458c52_verboseLabel_en-US" xlink:label="lab_isba_CommercialAndAgriculturalPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Commercial and Agricultural [Member]</link:label>
    <link:label id="lab_isba_CommercialAndAgriculturalPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_CommercialAndAgriculturalPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial And Agricultural Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialAndAgriculturalPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_CommercialAndAgriculturalPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial And Agricultural Portfolio Segment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialAndAgriculturalPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_CommercialAndAgriculturalPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialAndAgriculturalPortfolioSegmentMember" xlink:to="lab_isba_CommercialAndAgriculturalPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent_6deb178b-c305-4d01-b0a6-25d9d527e039_negatedTotalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="resource" xml:lang="en-US">Change in unrealized pension cost, net of tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent" xlink:to="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestExpenseAbstract_a6cc50ee-7894-46b6-b0d4-b0024b4e29e1_verboseLabel_en-US" xlink:label="lab_us-gaap_InterestExpenseAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interest expense</link:label>
    <link:label id="lab_us-gaap_InterestExpenseAbstract_label_en-US" xlink:label="lab_us-gaap_InterestExpenseAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestExpenseAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpenseAbstract" xlink:to="lab_us-gaap_InterestExpenseAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonEquityTierOneCapital_9e1ff107-6fb3-4de0-81f8-7ecfcede333a_terseLabel_en-US" xlink:label="lab_us-gaap_CommonEquityTierOneCapital" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common Equity Tier One Capital</link:label>
    <link:label id="lab_us-gaap_CommonEquityTierOneCapital_label_en-US" xlink:label="lab_us-gaap_CommonEquityTierOneCapital" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Common Equity Tier 1 Risk-Based Capital, Actual</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapital" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonEquityTierOneCapital"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonEquityTierOneCapital" xlink:to="lab_us-gaap_CommonEquityTierOneCapital" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember_6bb434e5-047a-4fda-b8a6-6a577774614f_verboseLabel_en-US" xlink:label="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Carrying Value [Member]</link:label>
    <link:label id="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember_label_en-US" xlink:label="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reported Value Measurement [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:to="lab_us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTable_464193e0-b8c6-486d-a60e-ef3d3fc93bbe_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Deferred Compensation Arrangement with Individual, Share-based Payments [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Deferred Compensation Arrangement with Individual, Share-Based Payments [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTable" xlink:to="lab_us-gaap_ScheduleOfDeferredCompensationArrangementWithIndividualShareBasedPaymentsTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_7f7e5b3d-0cf4-49c2-977b-42c6b341e4b7_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of premises and equipment</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StatementEquityComponentsAxis_6d64e2ba-c554-4589-a7fa-4f6a4baa636e_terseLabel_en-US" xlink:label="lab_us-gaap_StatementEquityComponentsAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity Components [Axis]</link:label>
    <link:label id="lab_us-gaap_StatementEquityComponentsAxis_label_en-US" xlink:label="lab_us-gaap_StatementEquityComponentsAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Components [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementEquityComponentsAxis" xlink:to="lab_us-gaap_StatementEquityComponentsAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_9bbc2fa4-e4c8-4c42-94b7-e673ae12da16_terseLabel_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Instruments [Domain]</link:label>
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_label_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instruments [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CondensedBalanceSheetStatementsCaptionsLineItems_81b8a4d6-6c98-40d2-9ef5-1fcbbf79b101_terseLabel_en-US" xlink:label="lab_srt_CondensedBalanceSheetStatementsCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Condensed Balance Sheet Statements, Captions [Line Items]</link:label>
    <link:label id="lab_srt_CondensedBalanceSheetStatementsCaptionsLineItems_label_en-US" xlink:label="lab_srt_CondensedBalanceSheetStatementsCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Balance Sheet Statements, Captions [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CondensedBalanceSheetStatementsCaptionsLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems" xlink:to="lab_srt_CondensedBalanceSheetStatementsCaptionsLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CreditLossFinancialInstrumentPolicyTextBlock_f80033ae-0bce-4687-9a16-3c9ef455714f_terseLabel_en-US" xlink:label="lab_us-gaap_CreditLossFinancialInstrumentPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit Loss, Financial Instrument</link:label>
    <link:label id="lab_us-gaap_CreditLossFinancialInstrumentPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_CreditLossFinancialInstrumentPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Loss, Financial Instrument [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossFinancialInstrumentPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CreditLossFinancialInstrumentPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CreditLossFinancialInstrumentPolicyTextBlock" xlink:to="lab_us-gaap_CreditLossFinancialInstrumentPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear_1300ead5-f22d-40d3-921a-14496b10da7f_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear" xlink:to="lab_us-gaap_FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntitySmallBusiness_718b4dce-a00d-41ca-9666-4d080b7af102_terseLabel_en-US" xlink:label="lab_dei_EntitySmallBusiness" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Small Business</link:label>
    <link:label id="lab_dei_EntitySmallBusiness_label_en-US" xlink:label="lab_dei_EntitySmallBusiness" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Small Business</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitySmallBusiness" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntitySmallBusiness"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntitySmallBusiness" xlink:to="lab_dei_EntitySmallBusiness" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RiskBasedRatiosAbstract_71212a28-8a0f-4e56-8821-5bcfd4be6319_terseLabel_en-US" xlink:label="lab_us-gaap_RiskBasedRatiosAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Banking Regulation, Risk-Based Information [Abstract]</link:label>
    <link:label id="lab_us-gaap_RiskBasedRatiosAbstract_label_en-US" xlink:label="lab_us-gaap_RiskBasedRatiosAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Risk-Based Information [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RiskBasedRatiosAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RiskBasedRatiosAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RiskBasedRatiosAbstract" xlink:to="lab_us-gaap_RiskBasedRatiosAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_LocalPhoneNumber_e0273ed3-ce74-4aae-8628-15975a91535e_terseLabel_en-US" xlink:label="lab_dei_LocalPhoneNumber" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Local Phone Number</link:label>
    <link:label id="lab_dei_LocalPhoneNumber_label_en-US" xlink:label="lab_dei_LocalPhoneNumber" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Local Phone Number</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_LocalPhoneNumber"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_LocalPhoneNumber" xlink:to="lab_dei_LocalPhoneNumber" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommonEquityTier1CapitalAbstract_1817a9d6-ca44-41ad-a43a-11eae52835f7_terseLabel_en-US" xlink:label="lab_isba_CommonEquityTier1CapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common Equity Tier 1 Capital [Abstract]</link:label>
    <link:label id="lab_isba_CommonEquityTier1CapitalAbstract_label_en-US" xlink:label="lab_isba_CommonEquityTier1CapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Equity Tier 1 Capital [Abstract]</link:label>
    <link:label id="lab_isba_CommonEquityTier1CapitalAbstract_documentation_en-US" xlink:label="lab_isba_CommonEquityTier1CapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Common Equity Tier 1 Capital [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommonEquityTier1CapitalAbstract" xlink:href="isba-20231231.xsd#isba_CommonEquityTier1CapitalAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommonEquityTier1CapitalAbstract" xlink:to="lab_isba_CommonEquityTier1CapitalAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable_e2feb108-e6be-4f2f-8fae-8185bd6f3efb_verboseLabel_en-US" xlink:label="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Taxable</link:label>
    <link:label id="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable_label_en-US" xlink:label="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest And Dividend Income, Securities, Operating, Available-for-sale, Taxable</link:label>
    <link:label id="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable_documentation_en-US" xlink:label="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Interest And Dividend Income, Securities, Operating, Available-for-sale, Taxable</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable" xlink:href="isba-20231231.xsd#isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable" xlink:to="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableThresholdPeriodPastDueWriteoff_c99e4b23-e7b3-4f59-8645-0b24856fb8d3_verboseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableThresholdPeriodPastDueWriteoff" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum days of consumer loan charged off</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableThresholdPeriodPastDueWriteoff_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableThresholdPeriodPastDueWriteoff" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Threshold Period Past Due, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableThresholdPeriodPastDueWriteoff" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableThresholdPeriodPastDueWriteoff"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableThresholdPeriodPastDueWriteoff" xlink:to="lab_us-gaap_FinancingReceivableThresholdPeriodPastDueWriteoff" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock_73345696-badc-406a-a1d9-2392173b26bb_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of compliance with regulatory capital requirements</link:label>
    <link:label id="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:to="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueByMeasurementFrequencyAxis_0e227cd3-5d10-42b2-8b51-fd3574f327b5_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByMeasurementFrequencyAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Measurement Frequency [Axis]</link:label>
    <link:label id="lab_us-gaap_FairValueByMeasurementFrequencyAxis_label_en-US" xlink:label="lab_us-gaap_FairValueByMeasurementFrequencyAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Measurement Frequency [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis" xlink:to="lab_us-gaap_FairValueByMeasurementFrequencyAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ExtendedMaturityMember_846f08e7-838e-47a7-8d3c-e8c81cadc912_terseLabel_en-US" xlink:label="lab_us-gaap_ExtendedMaturityMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Extended Maturity</link:label>
    <link:label id="lab_us-gaap_ExtendedMaturityMember_label_en-US" xlink:label="lab_us-gaap_ExtendedMaturityMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Extended Maturity [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExtendedMaturityMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ExtendedMaturityMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ExtendedMaturityMember" xlink:to="lab_us-gaap_ExtendedMaturityMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff_64b796ad-41d8-4b51-920b-4d7d9ba20f10_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff" xlink:to="lab_us-gaap_FinancingReceivableYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RetirementPlanTypeDomain_8515b9c0-c35d-4918-97d0-caa33e9798f8_terseLabel_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement Plan Type [Domain]</link:label>
    <link:label id="lab_us-gaap_RetirementPlanTypeDomain_label_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Plan Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanTypeDomain" xlink:to="lab_us-gaap_RetirementPlanTypeDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_a5e4ee78-f1a8-44fa-bd8e-f7d26e53cf94_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in Nonvested Restricted Stock Awards</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CashDonations_28e2f556-4de7-41e8-b26c-44f1a6701534_terseLabel_en-US" xlink:label="lab_isba_CashDonations" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Donations</link:label>
    <link:label id="lab_isba_CashDonations_label_en-US" xlink:label="lab_isba_CashDonations" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Donations</link:label>
    <link:label id="lab_isba_CashDonations_documentation_en-US" xlink:label="lab_isba_CashDonations" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash Donations</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CashDonations" xlink:href="isba-20231231.xsd#isba_CashDonations"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CashDonations" xlink:to="lab_isba_CashDonations" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_BankOwnedLifeInsuranceIncomeNetofExpense_80c10677-0031-4e74-a736-d10ee29a5a68_negatedLabel_en-US" xlink:label="lab_isba_BankOwnedLifeInsuranceIncomeNetofExpense" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Increase in cash value of corporate owned life insurance policies</link:label>
    <link:label id="lab_isba_BankOwnedLifeInsuranceIncomeNetofExpense_340bb9ab-54a6-4590-8da7-115f7265d690_terseLabel_en-US" xlink:label="lab_isba_BankOwnedLifeInsuranceIncomeNetofExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Bank Owned Life Insurance Income, Net of Expense</link:label>
    <link:label id="lab_isba_BankOwnedLifeInsuranceIncomeNetofExpense_label_en-US" xlink:label="lab_isba_BankOwnedLifeInsuranceIncomeNetofExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bank Owned Life Insurance Income, Net of Expense</link:label>
    <link:label id="lab_isba_BankOwnedLifeInsuranceIncomeNetofExpense_documentation_en-US" xlink:label="lab_isba_BankOwnedLifeInsuranceIncomeNetofExpense" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bank Owned Life Insurance Income, Net of Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_BankOwnedLifeInsuranceIncomeNetofExpense" xlink:href="isba-20231231.xsd#isba_BankOwnedLifeInsuranceIncomeNetofExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_BankOwnedLifeInsuranceIncomeNetofExpense" xlink:to="lab_isba_BankOwnedLifeInsuranceIncomeNetofExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Depreciation_dbd5b252-1199-41ed-9d3f-9c1a083b0e4e_verboseLabel_en-US" xlink:label="lab_us-gaap_Depreciation" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Depreciation</link:label>
    <link:label id="lab_us-gaap_Depreciation_e9f39e63-a408-4958-a3e3-213863592a11_terseLabel_en-US" xlink:label="lab_us-gaap_Depreciation" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Depreciation expense</link:label>
    <link:label id="lab_us-gaap_Depreciation_label_en-US" xlink:label="lab_us-gaap_Depreciation" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Depreciation</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Depreciation" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Depreciation"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Depreciation" xlink:to="lab_us-gaap_Depreciation" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CompensationAndRetirementDisclosureAbstract_5f096046-6f52-430f-bc46-87a5aa31a4cf_terseLabel_en-US" xlink:label="lab_us-gaap_CompensationAndRetirementDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement Benefits [Abstract]</link:label>
    <link:label id="lab_us-gaap_CompensationAndRetirementDisclosureAbstract_label_en-US" xlink:label="lab_us-gaap_CompensationAndRetirementDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Benefits [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CompensationAndRetirementDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CompensationAndRetirementDisclosureAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CompensationAndRetirementDisclosureAbstract" xlink:to="lab_us-gaap_CompensationAndRetirementDisclosureAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember_79b181db-33a6-42ab-9896-7f7342ad4d2c_terseLabel_en-US" xlink:label="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Portion at Fair Value Measurement [Member]</link:label>
    <link:label id="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember_label_en-US" xlink:label="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Portion at Fair Value Measurement [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:to="lab_us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff_a471ed97-04b2-4475-8d51-7cffb30a3b31_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff" xlink:to="lab_us-gaap_FinancingReceivableYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IntangibleAssetsNetIncludingGoodwill_40f27d90-6064-4b05-bf08-63714eec3a30_verboseLabel_en-US" xlink:label="lab_us-gaap_IntangibleAssetsNetIncludingGoodwill" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Goodwill and other intangible assets</link:label>
    <link:label id="lab_us-gaap_IntangibleAssetsNetIncludingGoodwill_label_en-US" xlink:label="lab_us-gaap_IntangibleAssetsNetIncludingGoodwill" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Intangible Assets, Net (Including Goodwill)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IntangibleAssetsNetIncludingGoodwill"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IntangibleAssetsNetIncludingGoodwill" xlink:to="lab_us-gaap_IntangibleAssetsNetIncludingGoodwill" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems_af65add8-de23-416f-8ab6-fb9636e57ead_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]</link:label>
    <link:label id="lab_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems_label_en-US" xlink:label="lab_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, off-Balance-Sheet Risks, Disclosure Information [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems" xlink:to="lab_us-gaap_FairValueOffBalanceSheetRisksDisclosureInformationLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ForeclosedAssetsFairValueDisclosure_c7ab28ea-1001-41b2-98b2-dedc5091c416_terseLabel_en-US" xlink:label="lab_isba_ForeclosedAssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreclosed assets</link:label>
    <link:label id="lab_isba_ForeclosedAssetsFairValueDisclosure_label_en-US" xlink:label="lab_isba_ForeclosedAssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Foreclosed Assets, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_ForeclosedAssetsFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_ForeclosedAssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Foreclosed Assets, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ForeclosedAssetsFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_ForeclosedAssetsFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ForeclosedAssetsFairValueDisclosure" xlink:to="lab_isba_ForeclosedAssetsFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ManagementFeeExpense_e9b4d13a-d8e3-46aa-8f2e-685eff788326_terseLabel_en-US" xlink:label="lab_us-gaap_ManagementFeeExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Management Fee Expense</link:label>
    <link:label id="lab_us-gaap_ManagementFeeExpense_label_en-US" xlink:label="lab_us-gaap_ManagementFeeExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Management Fee Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementFeeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ManagementFeeExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ManagementFeeExpense" xlink:to="lab_us-gaap_ManagementFeeExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Revenues_6f209857-eb26-4088-a6d1-88a3a787c9ce_terseLabel_en-US" xlink:label="lab_us-gaap_Revenues" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total income</link:label>
    <link:label id="lab_us-gaap_Revenues_label_en-US" xlink:label="lab_us-gaap_Revenues" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenues</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Revenues"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Revenues" xlink:to="lab_us-gaap_Revenues" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShortTermDebtLineItems_ab0bba1d-268d-46f1-a044-70f1aaeb778e_terseLabel_en-US" xlink:label="lab_us-gaap_ShortTermDebtLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Short-term Debt [Line Items]</link:label>
    <link:label id="lab_us-gaap_ShortTermDebtLineItems_label_en-US" xlink:label="lab_us-gaap_ShortTermDebtLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Debt [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermDebtLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShortTermDebtLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShortTermDebtLineItems" xlink:to="lab_us-gaap_ShortTermDebtLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations_748cbb81-e79d-481e-886b-0b9796a2bb18_verboseLabel_en-US" xlink:label="lab_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Federal income tax expense</link:label>
    <link:label id="lab_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations_fdb9b3ee-87fe-4b26-bf5b-7de6143b3b41_totalLabel_en-US" xlink:label="lab_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Income tax expense</link:label>
    <link:label id="lab_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations_02319a82-8707-48b2-ae2e-1f8d51a71384_negatedLabel_en-US" xlink:label="lab_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Federal income tax expense</link:label>
    <link:label id="lab_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations_label_en-US" xlink:label="lab_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Income Tax Expense (Benefit), Continuing Operations</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations" xlink:to="lab_us-gaap_FederalIncomeTaxExpenseBenefitContinuingOperations" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AwardTypeAxis_866caeb2-ab19-4f61-a719-e5e459a93ac3_terseLabel_en-US" xlink:label="lab_us-gaap_AwardTypeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Award Type [Axis]</link:label>
    <link:label id="lab_us-gaap_AwardTypeAxis_label_en-US" xlink:label="lab_us-gaap_AwardTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Award Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AwardTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AwardTypeAxis" xlink:to="lab_us-gaap_AwardTypeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SpecialMentionMember_75d7a6b9-3ba3-4c7b-974f-87c62c6849b7_terseLabel_en-US" xlink:label="lab_us-gaap_SpecialMentionMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Special Mention [Member]</link:label>
    <link:label id="lab_us-gaap_SpecialMentionMember_b23e25bf-f02a-4ad5-bf3a-b769af12dd8e_verboseLabel_en-US" xlink:label="lab_us-gaap_SpecialMentionMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">5 - Special mention [Member]</link:label>
    <link:label id="lab_us-gaap_SpecialMentionMember_label_en-US" xlink:label="lab_us-gaap_SpecialMentionMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Special Mention [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SpecialMentionMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SpecialMentionMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SpecialMentionMember" xlink:to="lab_us-gaap_SpecialMentionMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_23576a73-efe4-4b64-b631-54ed7dc5a0f0_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Granted (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesLineItems_728ce25e-ed29-4839-bd18-11043cb1b6fe_terseLabel_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances [Line Items]</link:label>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesLineItems_label_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankAdvancesLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalHomeLoanBankAdvancesLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalHomeLoanBankAdvancesLineItems" xlink:to="lab_us-gaap_FederalHomeLoanBankAdvancesLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialOtherPortfolioSegmentMember_7bd2b3b7-bc88-4e4b-ae5e-6eedcb2415da_terseLabel_en-US" xlink:label="lab_isba_CommercialOtherPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial Other Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialOtherPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_CommercialOtherPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Other Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialOtherPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_CommercialOtherPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial Other Portfolio Segment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialOtherPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_CommercialOtherPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialOtherPortfolioSegmentMember" xlink:to="lab_isba_CommercialOtherPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract_47416e53-863b-4c1e-acc3-ae53a83f1d24_verboseLabel_en-US" xlink:label="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">SUPPLEMENTAL NONCASH INFORMATION:</link:label>
    <link:label id="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract_label_en-US" xlink:label="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash Investing and Financing Items [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoncashInvestingAndFinancingItemsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:to="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock_ba59823d-07ce-4307-bf6d-983012fdcafd_terseLabel_en-US" xlink:label="lab_isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Individually Evaluated Collateral Dependent and Specific ACL</link:label>
    <link:label id="lab_isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock_label_en-US" xlink:label="lab_isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Amortized Cost Balance Of Financial Assets Considered Collateral Dependent [Table Text Block]</link:label>
    <link:label id="lab_isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock_documentation_en-US" xlink:label="lab_isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule Of Amortized Cost Balance Of Financial Assets Considered Collateral Dependent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock" xlink:href="isba-20231231.xsd#isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock" xlink:to="lab_isba_ScheduleOfAmortizedCostBalanceOfFinancialAssetsConsideredCollateralDependentTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations_d4eb7d79-1f8f-4f47-b29c-87309e728412_negatedLabel_en-US" xlink:label="lab_isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Common stock repurchased</link:label>
    <link:label id="lab_isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations_label_en-US" xlink:label="lab_isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments For Repurchase Of Common Stock, Excluding Stock For Deferred Compensation Obligations</link:label>
    <link:label id="lab_isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations_documentation_en-US" xlink:label="lab_isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Payments For Repurchase Of Common Stock, Excluding Stock For Deferred Compensation Obligations</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations" xlink:href="isba-20231231.xsd#isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations" xlink:to="lab_isba_PaymentsForRepurchaseOfCommonStockExcludingStockForDeferredCompensationObligations" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LoansReceivableCollateralizedByRealEstateMember_6bc00cfe-5f23-486a-96ee-36ce1addacf9_verboseLabel_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByRealEstateMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Real Estate [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByRealEstateMember_label_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByRealEstateMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Real Estate [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByRealEstateMember_documentation_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByRealEstateMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Real Estate [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LoansReceivableCollateralizedByRealEstateMember" xlink:href="isba-20231231.xsd#isba_LoansReceivableCollateralizedByRealEstateMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LoansReceivableCollateralizedByRealEstateMember" xlink:to="lab_isba_LoansReceivableCollateralizedByRealEstateMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalReserveBankAdvancesMember_60d962ae-bd7b-47cd-86e3-a7313330aac8_terseLabel_en-US" xlink:label="lab_us-gaap_FederalReserveBankAdvancesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal Reserve Bank Advances [Member]</link:label>
    <link:label id="lab_us-gaap_FederalReserveBankAdvancesMember_label_en-US" xlink:label="lab_us-gaap_FederalReserveBankAdvancesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Reserve Bank Advances [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalReserveBankAdvancesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalReserveBankAdvancesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalReserveBankAdvancesMember" xlink:to="lab_us-gaap_FederalReserveBankAdvancesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_c88e9dff-627a-4614-9b99-131c1865f066_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Hierarchy and NAV [Domain]</link:label>
    <link:label id="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_label_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Hierarchy and NAV [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_IcfrAuditorAttestationFlag_df9dee6b-24ad-400f-8650-e068d6fb1490_terseLabel_en-US" xlink:label="lab_dei_IcfrAuditorAttestationFlag" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">ICFR Auditor Attestation Flag</link:label>
    <link:label id="lab_dei_IcfrAuditorAttestationFlag_label_en-US" xlink:label="lab_dei_IcfrAuditorAttestationFlag" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">ICFR Auditor Attestation Flag</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_IcfrAuditorAttestationFlag" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_IcfrAuditorAttestationFlag"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_IcfrAuditorAttestationFlag" xlink:to="lab_dei_IcfrAuditorAttestationFlag" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_HedgingDesignationAxis_fad71b26-f7d6-4f52-bca8-f6c861c42ef7_terseLabel_en-US" xlink:label="lab_us-gaap_HedgingDesignationAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Hedging Designation [Axis]</link:label>
    <link:label id="lab_us-gaap_HedgingDesignationAxis_label_en-US" xlink:label="lab_us-gaap_HedgingDesignationAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Hedging Designation [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_HedgingDesignationAxis" xlink:to="lab_us-gaap_HedgingDesignationAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentGross_a3580607-3159-4df9-961b-a76c0b58af63_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentGross" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentGross_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentGross" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Gross</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentGross" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentGross" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer_46b4f0a5-3f14-444a-9fc9-aaf35e090cab_terseLabel_en-US" xlink:label="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer_label_en-US" xlink:label="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer_documentation_en-US" xlink:label="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:href="isba-20231231.xsd#isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:to="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_7b234c37-4c35-4fef-bc5f-daa77f03923a_verboseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Related Party Transactions</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transactions Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionsDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:to="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer_bfcb983a-f0fc-42e8-bd2e-d36ae3c29c5c_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Contributions</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer_5bfcce02-c351-4bcf-90ef-5ee0a100d8ae_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contributions</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Contributions by Employer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanContributionsByEmployer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:to="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_f8d26f08-b20b-459b-9e4f-568a10cc3f7e_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Expected return on plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Return (Loss) on Plan Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_77a30e04-7c2c-44a6-a667-f1a0daf92785_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Components of the consolidated provision for federal income taxes</link:label>
    <link:label id="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1_dc4f510d-38bb-4a39-ade6-d0093e2b7db6_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Individually evaluated for impairment, ACL</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1" xlink:to="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_HighSatisfactoryRatingMember_d27c6bb3-ebd3-4275-99ab-650792d4ba91_terseLabel_en-US" xlink:label="lab_isba_HighSatisfactoryRatingMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">High Satisfactory Rating [Member]</link:label>
    <link:label id="lab_isba_HighSatisfactoryRatingMember_label_en-US" xlink:label="lab_isba_HighSatisfactoryRatingMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Satisfactory Rating [Member]</link:label>
    <link:label id="lab_isba_HighSatisfactoryRatingMember_documentation_en-US" xlink:label="lab_isba_HighSatisfactoryRatingMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High satisfactory rating.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_HighSatisfactoryRatingMember" xlink:href="isba-20231231.xsd#isba_HighSatisfactoryRatingMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_HighSatisfactoryRatingMember" xlink:to="lab_isba_HighSatisfactoryRatingMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableModificationWeightedAverageExtensionTerm_179950b9-2ef4-4154-952b-5db29b12b177_terseLabel_en-US" xlink:label="lab_isba_FinancingReceivableModificationWeightedAverageExtensionTerm" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable Modification Weighted Average Extension Term</link:label>
    <link:label id="lab_isba_FinancingReceivableModificationWeightedAverageExtensionTerm_label_en-US" xlink:label="lab_isba_FinancingReceivableModificationWeightedAverageExtensionTerm" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable Modification Weighted Average Extension Term</link:label>
    <link:label id="lab_isba_FinancingReceivableModificationWeightedAverageExtensionTerm_documentation_en-US" xlink:label="lab_isba_FinancingReceivableModificationWeightedAverageExtensionTerm" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable Modification Weighted Average Extension Term</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableModificationWeightedAverageExtensionTerm" xlink:href="isba-20231231.xsd#isba_FinancingReceivableModificationWeightedAverageExtensionTerm"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableModificationWeightedAverageExtensionTerm" xlink:to="lab_isba_FinancingReceivableModificationWeightedAverageExtensionTerm" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CollateralizedMortgageObligationsMember_bdf82baf-1c8a-40af-9c17-f499bbf4ffa7_verboseLabel_en-US" xlink:label="lab_us-gaap_CollateralizedMortgageObligationsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Collateralized mortgage obligations [Member]</link:label>
    <link:label id="lab_us-gaap_CollateralizedMortgageObligationsMember_009b35b6-1523-4ccb-87cd-7685e9cfa3a5_terseLabel_en-US" xlink:label="lab_us-gaap_CollateralizedMortgageObligationsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Collateralized Mortgage Obligations [Member]</link:label>
    <link:label id="lab_us-gaap_CollateralizedMortgageObligationsMember_label_en-US" xlink:label="lab_us-gaap_CollateralizedMortgageObligationsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Collateralized Mortgage Obligations [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralizedMortgageObligationsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CollateralizedMortgageObligationsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CollateralizedMortgageObligationsMember" xlink:to="lab_us-gaap_CollateralizedMortgageObligationsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer_dd668713-9ed9-45c3-8d8b-be16161f2f25_terseLabel_en-US" xlink:label="lab_isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacy</link:label>
    <link:label id="lab_isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer_label_en-US" xlink:label="lab_isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer_documentation_en-US" xlink:label="lab_isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer" xlink:href="isba-20231231.xsd#isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer" xlink:to="lab_isba_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumPlusCapitalConservationBuffer" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableLoanToValueRatioMaximum_1da351db-3840-4263-a03a-47f74a3c0682_verboseLabel_en-US" xlink:label="lab_isba_FinancingReceivableLoanToValueRatioMaximum" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum percentage of loan</link:label>
    <link:label id="lab_isba_FinancingReceivableLoanToValueRatioMaximum_label_en-US" xlink:label="lab_isba_FinancingReceivableLoanToValueRatioMaximum" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Loan To Value Ratio, Maximum</link:label>
    <link:label id="lab_isba_FinancingReceivableLoanToValueRatioMaximum_documentation_en-US" xlink:label="lab_isba_FinancingReceivableLoanToValueRatioMaximum" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable, Loan To Value Ratio, Maximum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableLoanToValueRatioMaximum" xlink:href="isba-20231231.xsd#isba_FinancingReceivableLoanToValueRatioMaximum"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableLoanToValueRatioMaximum" xlink:to="lab_isba_FinancingReceivableLoanToValueRatioMaximum" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsNet_61285d9f-fec3-4287-8108-2e878c3904ad_totalLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net Intangible Assets</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsNet_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentLineItems_35ef6606-18cf-43f0-99e8-a58ad3de7b38_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Line Items]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentLineItems_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmount_67bb93eb-ce5f-498d-9771-64aaac104301_totalLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmount" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net loans</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmount_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Net Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableNetReportedAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableNetReportedAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableNetReportedAmount" xlink:to="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_RepurchaseAgreementCounterpartyNameDomain_ed86e541-2f22-4e80-ba8b-e6e44f0e2c07_terseLabel_en-US" xlink:label="lab_srt_RepurchaseAgreementCounterpartyNameDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Counterparty Name [Domain]</link:label>
    <link:label id="lab_srt_RepurchaseAgreementCounterpartyNameDomain_label_en-US" xlink:label="lab_srt_RepurchaseAgreementCounterpartyNameDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Counterparty Name [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain" xlink:to="lab_srt_RepurchaseAgreementCounterpartyNameDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InternalCreditAssessmentAxis_85a4a70a-82e4-49de-8916-185960919179_terseLabel_en-US" xlink:label="lab_us-gaap_InternalCreditAssessmentAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Internal Credit Assessment [Axis]</link:label>
    <link:label id="lab_us-gaap_InternalCreditAssessmentAxis_label_en-US" xlink:label="lab_us-gaap_InternalCreditAssessmentAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Internal Credit Assessment [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InternalCreditAssessmentAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis" xlink:to="lab_us-gaap_InternalCreditAssessmentAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DerivativeAssetNotionalAmount_c2e2825f-73c6-4666-98c6-aa97da9f99de_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeAssetNotionalAmount" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative Asset, Notional Amount</link:label>
    <link:label id="lab_us-gaap_DerivativeAssetNotionalAmount_5c66674c-027f-441b-89fb-8e7e605e3216_verboseLabel_en-US" xlink:label="lab_us-gaap_DerivativeAssetNotionalAmount" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Notional Amount of undesignated commitments</link:label>
    <link:label id="lab_us-gaap_DerivativeAssetNotionalAmount_label_en-US" xlink:label="lab_us-gaap_DerivativeAssetNotionalAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Asset, Notional Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetNotionalAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DerivativeAssetNotionalAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeAssetNotionalAmount" xlink:to="lab_us-gaap_DerivativeAssetNotionalAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_f6bf7f8b-1b59-4045-995e-79b9f12c7ac7_verboseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Amortization</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract_061872b9-5f84-40a6-92d0-43d77e79a271_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Actuarial assumptions used in determining the projected benefit obligation</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract" xlink:to="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeTaxReconciliationNondeductibleExpense_b2de4d83-3c1c-4ca4-a599-f34023da8dc2_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxReconciliationNondeductibleExpense" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Effect of nondeductible expenses</link:label>
    <link:label id="lab_us-gaap_IncomeTaxReconciliationNondeductibleExpense_label_en-US" xlink:label="lab_us-gaap_IncomeTaxReconciliationNondeductibleExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense" xlink:to="lab_us-gaap_IncomeTaxReconciliationNondeductibleExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementPlansPensionsPolicy_1110aa52-6c87-477a-8325-e545b85896af_terseLabel_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementPlansPensionsPolicy" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">DEFINED BENEFIT PENSION PLAN</link:label>
    <link:label id="lab_us-gaap_PensionAndOtherPostretirementPlansPensionsPolicy_label_en-US" xlink:label="lab_us-gaap_PensionAndOtherPostretirementPlansPensionsPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pension and Other Postretirement Plans, Pensions, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PensionAndOtherPostretirementPlansPensionsPolicy" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PensionAndOtherPostretirementPlansPensionsPolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementPlansPensionsPolicy" xlink:to="lab_us-gaap_PensionAndOtherPostretirementPlansPensionsPolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions_4e2e2f63-3889-4685-a990-ef9701503830_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NonperformingFinancingReceivableMember_389159c2-c201-4646-8c52-0bd2dde00434_terseLabel_en-US" xlink:label="lab_us-gaap_NonperformingFinancingReceivableMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Nonperforming Financial Instruments</link:label>
    <link:label id="lab_us-gaap_NonperformingFinancingReceivableMember_label_en-US" xlink:label="lab_us-gaap_NonperformingFinancingReceivableMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Nonperforming Financial Instruments [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonperformingFinancingReceivableMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NonperformingFinancingReceivableMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NonperformingFinancingReceivableMember" xlink:to="lab_us-gaap_NonperformingFinancingReceivableMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_3c596cdf-6815-45d5-a78e-26ac5c23edaa_verboseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accumulated other comprehensive income loss</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_0530798b-d21e-4d2d-95d2-7a71b1507281_periodStartLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_c2603557-ed63-497e-9bc2-e8054cd31a19_periodEndLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_label_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss), Net of Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_74993ba0-9b66-4d42-aa34-9e55f547a4a4_verboseLabel_en-US" xlink:label="lab_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio</link:label>
    <link:label id="lab_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_label_en-US" xlink:label="lab_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Total Risk-Based Capital Ratio, Well Capitalized, Minimum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:to="lab_us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary_f91e84ba-6ae8-4e8d-b447-e0b941ab24c3_terseLabel_en-US" xlink:label="lab_isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income before equity in undistributed earnings of subsidiaries</link:label>
    <link:label id="lab_isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary_label_en-US" xlink:label="lab_isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Before Equity In Undistributed Net Income Of Subsidiary</link:label>
    <link:label id="lab_isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary_documentation_en-US" xlink:label="lab_isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Income Before Equity In Undistributed Net Income Of Subsidiary</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary" xlink:href="isba-20231231.xsd#isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary" xlink:to="lab_isba_IncomeBeforeEquityInUndistributedNetIncomeOfSubsidiary" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CostsAndExpenses_0cd10b41-071f-4aae-8684-2160a88f1c0c_terseLabel_en-US" xlink:label="lab_us-gaap_CostsAndExpenses" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total expenses</link:label>
    <link:label id="lab_us-gaap_CostsAndExpenses_label_en-US" xlink:label="lab_us-gaap_CostsAndExpenses" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Costs and Expenses</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpenses" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CostsAndExpenses"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostsAndExpenses" xlink:to="lab_us-gaap_CostsAndExpenses" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment_cfec53e0-73ee-4d9f-8d64-490cb17dad1b_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Individually Evaluated for Impairment, Loans</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Individually Evaluated for Impairment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment" xlink:to="lab_us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_d7e09b13-fdb8-4003-967b-2cafbbbb4892_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Settlement loss</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_8f474141-7672-4d4d-9ff5-103a54ef5904_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1" xlink:to="lab_us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_MaximumMember_2da9bc35-de6c-426c-b9ce-3f41493972d8_verboseLabel_en-US" xlink:label="lab_srt_MaximumMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum [Member]</link:label>
    <link:label id="lab_srt_MaximumMember_ebdd8ad4-7450-4066-95ec-5d5f842380be_terseLabel_en-US" xlink:label="lab_srt_MaximumMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Maximum [Member]</link:label>
    <link:label id="lab_srt_MaximumMember_label_en-US" xlink:label="lab_srt_MaximumMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Maximum [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MaximumMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_MaximumMember" xlink:to="lab_srt_MaximumMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation_853eae74-cd17-4c47-b3b5-c2c2746e070a_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred directors' fees</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Compensation</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation" xlink:to="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentType_15057de8-dd13-4710-83eb-5feaf5aef4b5_terseLabel_en-US" xlink:label="lab_dei_DocumentType" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Type</link:label>
    <link:label id="lab_dei_DocumentType_label_en-US" xlink:label="lab_dei_DocumentType" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Type</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentType"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentType" xlink:to="lab_dei_DocumentType" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock_86fce8c9-820e-4ca1-8d25-a864c5c0af75_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of related party transactions</link:label>
    <link:label id="lab_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Related Party Transactions [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_c103600c-16c7-48c5-85b1-2e1f603be202_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Table]</link:label>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable_label_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:to="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TransferToOtherRealEstate_faa13837-feb2-4a92-b5dd-40280db2abce_terseLabel_en-US" xlink:label="lab_us-gaap_TransferToOtherRealEstate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Transfers of loans to foreclosed assets</link:label>
    <link:label id="lab_us-gaap_TransferToOtherRealEstate_label_en-US" xlink:label="lab_us-gaap_TransferToOtherRealEstate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Real Estate Owned, Transfer to Real Estate Owned</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransferToOtherRealEstate" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TransferToOtherRealEstate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransferToOtherRealEstate" xlink:to="lab_us-gaap_TransferToOtherRealEstate" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CumulativeEffectPeriodOfAdoptionDomain_77bbc934-8ba2-4ece-bcda-b6e622f8caf4_terseLabel_en-US" xlink:label="lab_srt_CumulativeEffectPeriodOfAdoptionDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cumulative Effect, Period of Adoption [Domain]</link:label>
    <link:label id="lab_srt_CumulativeEffectPeriodOfAdoptionDomain_label_en-US" xlink:label="lab_srt_CumulativeEffectPeriodOfAdoptionDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cumulative Effect, Period of Adoption [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionDomain" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionDomain" xlink:to="lab_srt_CumulativeEffectPeriodOfAdoptionDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost_24b1d6ff-361c-4070-88d1-256f12cc2433_verboseLabel_en-US" xlink:label="lab_isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Periodic policy maintenance costs</link:label>
    <link:label id="lab_isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost_label_en-US" xlink:label="lab_isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Life Insurance, Corporate or Bank Owned, Maintenance Cost</link:label>
    <link:label id="lab_isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost_documentation_en-US" xlink:label="lab_isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Life Insurance, Corporate or Bank Owned, Maintenance Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost" xlink:href="isba-20231231.xsd#isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost" xlink:to="lab_isba_LifeInsuranceCorporateorBankOwnedMaintenanceCost" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CurrentFederalTaxExpenseBenefit_4b5f9873-1931-474d-b90f-649a86d9c3e3_verboseLabel_en-US" xlink:label="lab_us-gaap_CurrentFederalTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Currently payable</link:label>
    <link:label id="lab_us-gaap_CurrentFederalTaxExpenseBenefit_label_en-US" xlink:label="lab_us-gaap_CurrentFederalTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current Federal Tax Expense (Benefit)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrentFederalTaxExpenseBenefit" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CurrentFederalTaxExpenseBenefit"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentFederalTaxExpenseBenefit" xlink:to="lab_us-gaap_CurrentFederalTaxExpenseBenefit" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_69cc21ca-1c3e-4405-a783-e40e4bcf3d18_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Purchases</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Debt Securities, Available-for-Sale</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt" xlink:to="lab_us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ServicingAssetAtAmortizedValue_5b5f8740-5af1-41bc-855b-f37bd1a51895_verboseLabel_en-US" xlink:label="lab_us-gaap_ServicingAssetAtAmortizedValue" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Capitalized mortgage loans on real estate carrying amount</link:label>
    <link:label id="lab_us-gaap_ServicingAssetAtAmortizedValue_label_en-US" xlink:label="lab_us-gaap_ServicingAssetAtAmortizedValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Servicing Asset at Amortized Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetAtAmortizedValue" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ServicingAssetAtAmortizedValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ServicingAssetAtAmortizedValue" xlink:to="lab_us-gaap_ServicingAssetAtAmortizedValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock_d67fde94-3fb5-43dc-8fc3-c270e65f937f_terseLabel_en-US" xlink:label="lab_us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Troubled Debt Restructurings on Financing Receivables [Table Text Block]</link:label>
    <link:label id="lab_us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock_label_en-US" xlink:label="lab_us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Modified [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock" xlink:to="lab_us-gaap_TroubledDebtRestructuringsOnFinancingReceivablesTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_A9LossMember_a10fcc3c-d44a-4b5e-bde4-f3599522cfb3_terseLabel_en-US" xlink:label="lab_isba_A9LossMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">9 - Loss</link:label>
    <link:label id="lab_isba_A9LossMember_label_en-US" xlink:label="lab_isba_A9LossMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">9 - Loss [Member]</link:label>
    <link:label id="lab_isba_A9LossMember_documentation_en-US" xlink:label="lab_isba_A9LossMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">9 - Loss</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_A9LossMember" xlink:href="isba-20231231.xsd#isba_A9LossMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_A9LossMember" xlink:to="lab_isba_A9LossMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DerivativeTable_0fbcf1eb-03be-4152-9bcc-6f950ee53def_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative [Table]</link:label>
    <link:label id="lab_us-gaap_DerivativeTable_label_en-US" xlink:label="lab_us-gaap_DerivativeTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DerivativeTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeTable" xlink:to="lab_us-gaap_DerivativeTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CustomerConcentrationRiskMember_05d428bd-f1d5-4a36-a50b-ca178ab1441c_terseLabel_en-US" xlink:label="lab_us-gaap_CustomerConcentrationRiskMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Customer Concentration Risk [Member]</link:label>
    <link:label id="lab_us-gaap_CustomerConcentrationRiskMember_label_en-US" xlink:label="lab_us-gaap_CustomerConcentrationRiskMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Customer Concentration Risk [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CustomerConcentrationRiskMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CustomerConcentrationRiskMember" xlink:to="lab_us-gaap_CustomerConcentrationRiskMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CostsAndExpensesAbstract_68c50fac-8c96-4803-b1d2-a4ae9e139914_verboseLabel_en-US" xlink:label="lab_us-gaap_CostsAndExpensesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Expenses</link:label>
    <link:label id="lab_us-gaap_CostsAndExpensesAbstract_label_en-US" xlink:label="lab_us-gaap_CostsAndExpensesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Costs and Expenses [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostsAndExpensesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CostsAndExpensesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostsAndExpensesAbstract" xlink:to="lab_us-gaap_CostsAndExpensesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestIncomeOperating_d132f1ab-99d9-49d4-b632-bc9f7393ace9_verboseLabel_en-US" xlink:label="lab_us-gaap_InterestIncomeOperating" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interest income</link:label>
    <link:label id="lab_us-gaap_InterestIncomeOperating_label_en-US" xlink:label="lab_us-gaap_InterestIncomeOperating" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Income, Operating</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeOperating" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestIncomeOperating"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestIncomeOperating" xlink:to="lab_us-gaap_InterestIncomeOperating" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearTwo_305e3135-c1e6-4b5f-9784-37ed4484033b_verboseLabel_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearTwo" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year Two</link:label>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearTwo_label_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearTwo" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Time Deposit Maturities, Year Two</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearTwo" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TimeDepositMaturitiesYearTwo"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimeDepositMaturitiesYearTwo" xlink:to="lab_us-gaap_TimeDepositMaturitiesYearTwo" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss_8abe9420-6200-4172-9794-06684b5b520a_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Actuarial (gain) loss</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanActuarialGainLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:to="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RelatedPartyDomain_370eaa83-eb07-4f41-b5bc-54b10c43e722_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party [Domain]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyDomain_label_en-US" xlink:label="lab_us-gaap_RelatedPartyDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party, Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyDomain" xlink:to="lab_us-gaap_RelatedPartyDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan_04363bb8-ecd0-451d-950e-a147a21a25bd_terseLabel_en-US" xlink:label="lab_isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan</link:label>
    <link:label id="lab_isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan_label_en-US" xlink:label="lab_isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan</link:label>
    <link:label id="lab_isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan_documentation_en-US" xlink:label="lab_isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan" xlink:href="isba-20231231.xsd#isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan" xlink:to="lab_isba_LoanPortfolioClassesAndSegmentsAsPercentageofAggregateLoan" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_e684d8c1-d3c3-4143-bb3a-b18e95f10804_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio</link:label>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets_label_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Risk-Based Capital Ratio, Well Capitalized, Minimum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:to="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommercialPortfolioSegmentMember_2d4e0d99-b31d-4abf-a36f-d3f23c99a60a_terseLabel_en-US" xlink:label="lab_us-gaap_CommercialPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial [Member]</link:label>
    <link:label id="lab_us-gaap_CommercialPortfolioSegmentMember_61e6210a-2f6c-4b99-b0aa-32dda794bf94_verboseLabel_en-US" xlink:label="lab_us-gaap_CommercialPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total commercial [Member]</link:label>
    <link:label id="lab_us-gaap_CommercialPortfolioSegmentMember_label_en-US" xlink:label="lab_us-gaap_CommercialPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Portfolio Segment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommercialPortfolioSegmentMember" xlink:to="lab_us-gaap_CommercialPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_MortgagesHeldForSaleFairValueDisclosure_7dbf20ea-143b-40df-a254-679860832d43_verboseLabel_en-US" xlink:label="lab_us-gaap_MortgagesHeldForSaleFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Mortgage loans AFS</link:label>
    <link:label id="lab_us-gaap_MortgagesHeldForSaleFairValueDisclosure_label_en-US" xlink:label="lab_us-gaap_MortgagesHeldForSaleFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loan, Mortgage, Held-for-Sale, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgagesHeldForSaleFairValueDisclosure" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MortgagesHeldForSaleFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MortgagesHeldForSaleFairValueDisclosure" xlink:to="lab_us-gaap_MortgagesHeldForSaleFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest_7efdfc16-e011-4a43-8fe8-184ac14ab4c4_terseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest" xlink:to="lab_us-gaap_LoansAndLeasesReceivableImpairedNonperformingNonaccrualOfInterest" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeTaxDisclosureAbstract_2eab16ec-4158-4498-81d4-1ae9bef0efa4_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Tax Disclosure [Abstract]</link:label>
    <link:label id="lab_us-gaap_IncomeTaxDisclosureAbstract_label_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Disclosure [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxDisclosureAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract" xlink:to="lab_us-gaap_IncomeTaxDisclosureAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_MortgageServicingRightsMSRImpairmentRecovery_15327f34-74ec-4ac3-ad86-63261b745a94_terseLabel_en-US" xlink:label="lab_us-gaap_MortgageServicingRightsMSRImpairmentRecovery" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">OMSR Impairment</link:label>
    <link:label id="lab_us-gaap_MortgageServicingRightsMSRImpairmentRecovery_label_en-US" xlink:label="lab_us-gaap_MortgageServicingRightsMSRImpairmentRecovery" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Mortgage Servicing Rights (MSR) Impairment (Recovery)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageServicingRightsMSRImpairmentRecovery" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MortgageServicingRightsMSRImpairmentRecovery"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MortgageServicingRightsMSRImpairmentRecovery" xlink:to="lab_us-gaap_MortgageServicingRightsMSRImpairmentRecovery" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_RevolvingLoansConvertedToTermMember_e45de78e-cba7-4921-a60f-07a30b250d37_terseLabel_en-US" xlink:label="lab_isba_RevolvingLoansConvertedToTermMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revolving Loans Converted to Term</link:label>
    <link:label id="lab_isba_RevolvingLoansConvertedToTermMember_label_en-US" xlink:label="lab_isba_RevolvingLoansConvertedToTermMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revolving Loans Converted to Term [Member]</link:label>
    <link:label id="lab_isba_RevolvingLoansConvertedToTermMember_documentation_en-US" xlink:label="lab_isba_RevolvingLoansConvertedToTermMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Revolving Loans Converted to Term</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_RevolvingLoansConvertedToTermMember" xlink:href="isba-20231231.xsd#isba_RevolvingLoansConvertedToTermMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_RevolvingLoansConvertedToTermMember" xlink:to="lab_isba_RevolvingLoansConvertedToTermMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfFederalHomeLoanBankStock_66dcfe90-4b94-465d-af55-bb02bcc30797_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfFederalHomeLoanBankStock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from Sale of Federal Home Loan Bank Stock</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfFederalHomeLoanBankStock_label_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfFederalHomeLoanBankStock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Sale of Federal Home Loan Bank Stock</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfFederalHomeLoanBankStock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromSaleOfFederalHomeLoanBankStock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleOfFederalHomeLoanBankStock" xlink:to="lab_us-gaap_ProceedsFromSaleOfFederalHomeLoanBankStock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum_582c610e-e2c2-4901-abe0-085390855f0f_verboseLabel_en-US" xlink:label="lab_isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum percentage of principal, interest, taxes and hazard insurance on property over gross income</link:label>
    <link:label id="lab_isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum_label_en-US" xlink:label="lab_isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Payment Amount To Gross Income Ratio, Maximum</link:label>
    <link:label id="lab_isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum_documentation_en-US" xlink:label="lab_isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable, Payment Amount To Gross Income Ratio, Maximum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum" xlink:href="isba-20231231.xsd#isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum" xlink:to="lab_isba_FinancingReceivablePaymentAmountToGrossIncomeRatioMaximum" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_aa770207-ed9b-4878-aa30-205f9c8e9b9b_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loan Composition</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityTaxIdentificationNumber_b625cd42-4234-4fdd-821a-d80dccce4cd7_terseLabel_en-US" xlink:label="lab_dei_EntityTaxIdentificationNumber" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Tax Identification Number</link:label>
    <link:label id="lab_dei_EntityTaxIdentificationNumber_label_en-US" xlink:label="lab_dei_EntityTaxIdentificationNumber" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Tax Identification Number</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityTaxIdentificationNumber" xlink:to="lab_dei_EntityTaxIdentificationNumber" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_RangeAxis_a0ddef20-6cc4-4b5c-bab2-40d8dc0ea01f_terseLabel_en-US" xlink:label="lab_srt_RangeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statistical Measurement [Axis]</link:label>
    <link:label id="lab_srt_RangeAxis_label_en-US" xlink:label="lab_srt_RangeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statistical Measurement [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RangeAxis" xlink:to="lab_srt_RangeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CumulativeEffectPeriodOfAdoptionAxis_e1b1fcd1-e09c-482f-bfa1-82c601cb64c6_terseLabel_en-US" xlink:label="lab_srt_CumulativeEffectPeriodOfAdoptionAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cumulative Effect, Period of Adoption [Axis]</link:label>
    <link:label id="lab_srt_CumulativeEffectPeriodOfAdoptionAxis_label_en-US" xlink:label="lab_srt_CumulativeEffectPeriodOfAdoptionAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cumulative Effect, Period of Adoption [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionAxis" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionAxis" xlink:to="lab_srt_CumulativeEffectPeriodOfAdoptionAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityInteractiveDataCurrent_0ec2abdf-543c-40fe-b4ca-7c891788f823_terseLabel_en-US" xlink:label="lab_dei_EntityInteractiveDataCurrent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Interactive Data Current</link:label>
    <link:label id="lab_dei_EntityInteractiveDataCurrent_label_en-US" xlink:label="lab_dei_EntityInteractiveDataCurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Interactive Data Current</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInteractiveDataCurrent" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityInteractiveDataCurrent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityInteractiveDataCurrent" xlink:to="lab_dei_EntityInteractiveDataCurrent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DisaggregationOfRevenueTable_42d61fb1-0820-4d1d-a96a-b35b6f8dd970_terseLabel_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disaggregation of Revenue [Table]</link:label>
    <link:label id="lab_us-gaap_DisaggregationOfRevenueTable_label_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disaggregation of Revenue [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable" xlink:to="lab_us-gaap_DisaggregationOfRevenueTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfRealizedGainLossTableTextBlock_c3b88926-c974-4e9b-91c4-4b2f6713ec82_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfRealizedGainLossTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of the activity related to sales of available-for-sale securities</link:label>
    <link:label id="lab_us-gaap_ScheduleOfRealizedGainLossTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfRealizedGainLossTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Realized Gain (Loss) [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRealizedGainLossTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfRealizedGainLossTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRealizedGainLossTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfRealizedGainLossTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ResidentialPortfolioSegmentMember_f3a97ed1-c12f-4e8a-a178-6e424f8731ea_terseLabel_en-US" xlink:label="lab_us-gaap_ResidentialPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Residential Real Estate [Member]</link:label>
    <link:label id="lab_us-gaap_ResidentialPortfolioSegmentMember_label_en-US" xlink:label="lab_us-gaap_ResidentialPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Residential Portfolio Segment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ResidentialPortfolioSegmentMember" xlink:to="lab_us-gaap_ResidentialPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember_a00c0620-3ad1-4a34-a5be-91aadf66d91a_terseLabel_en-US" xlink:label="lab_isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, Owner Occupied, Portfolio Segment</link:label>
    <link:label id="lab_isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, Owner Occupied, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, Owner Occupied, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember" xlink:to="lab_isba_CommercialRealEstateOwnerOccupiedPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableRevolving_4848cf78-8d8a-4dc6-947a-2209292b4f56_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRevolving" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Revolving</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRevolving_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableRevolving" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Revolving</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRevolving" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableRevolving"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableRevolving" xlink:to="lab_us-gaap_FinancingReceivableRevolving" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleTable_9f39b305-42a3-44cf-92a7-697c7ad22dd7_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Available-for-sale Securities [Table]</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleTable_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis_f647c823-836d-478d-ac45-0b21c723f8c3_verboseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maturing, After One Year But Within Five Years</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_98d52c2e-af77-4de6-8dca-f09b99b20708_verboseLabel_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">ACQUISITION INTANGIBLES AND GOODWILL</link:label>
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill and Intangible Assets, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock" xlink:to="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityWellKnownSeasonedIssuer_c8521f48-8fa7-4a7a-a462-1585b5dcb345_terseLabel_en-US" xlink:label="lab_dei_EntityWellKnownSeasonedIssuer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Well-known Seasoned Issuer</link:label>
    <link:label id="lab_dei_EntityWellKnownSeasonedIssuer_label_en-US" xlink:label="lab_dei_EntityWellKnownSeasonedIssuer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Well-known Seasoned Issuer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityWellKnownSeasonedIssuer" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityWellKnownSeasonedIssuer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityWellKnownSeasonedIssuer" xlink:to="lab_dei_EntityWellKnownSeasonedIssuer" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue_becb72a4-52af-442c-85cd-c345f8265e86_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_c1115306-96ab-4ef7-ae59-f69124019174_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ResidentialPrivatelyInsuredFinancingReceivableMember_11b32744-506e-4802-98b0-e48926a633e0_terseLabel_en-US" xlink:label="lab_isba_ResidentialPrivatelyInsuredFinancingReceivableMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Residential, Privately Insured, Financing Receivable [Member]</link:label>
    <link:label id="lab_isba_ResidentialPrivatelyInsuredFinancingReceivableMember_label_en-US" xlink:label="lab_isba_ResidentialPrivatelyInsuredFinancingReceivableMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Residential, Privately Insured, Financing Receivable [Member]</link:label>
    <link:label id="lab_isba_ResidentialPrivatelyInsuredFinancingReceivableMember_documentation_en-US" xlink:label="lab_isba_ResidentialPrivatelyInsuredFinancingReceivableMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Residential, Privately Insured, Financing Receivable [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ResidentialPrivatelyInsuredFinancingReceivableMember" xlink:href="isba-20231231.xsd#isba_ResidentialPrivatelyInsuredFinancingReceivableMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ResidentialPrivatelyInsuredFinancingReceivableMember" xlink:to="lab_isba_ResidentialPrivatelyInsuredFinancingReceivableMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_39b1d850-4e6c-4636-afc4-34c22ccd7242_terseLabel_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies Disclosure [Abstract]</link:label>
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_label_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies Disclosure [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale_4bbbc1d0-cdb6-43fa-a4fb-14308eb13f95_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Origination of loans held for sale</link:label>
    <link:label id="lab_us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale_c7f0d17e-4795-464f-b035-17557993d664_terseLabel_en-US" xlink:label="lab_us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Payments for Origination of Mortgage Loans Held-for-sale</link:label>
    <link:label id="lab_us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale_label_en-US" xlink:label="lab_us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payment for Origination, Loan, Mortgage, Held-for-Sale</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale" xlink:to="lab_us-gaap_PaymentsForOriginationOfMortgageLoansHeldForSale" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityIncorporationStateCountryCode_5cc311e7-bf2f-4d63-9b77-734e41104fd5_terseLabel_en-US" xlink:label="lab_dei_EntityIncorporationStateCountryCode" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Incorporation, State or Country Code</link:label>
    <link:label id="lab_dei_EntityIncorporationStateCountryCode_label_en-US" xlink:label="lab_dei_EntityIncorporationStateCountryCode" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Incorporation, State or Country Code</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityIncorporationStateCountryCode" xlink:to="lab_dei_EntityIncorporationStateCountryCode" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NoninterestIncome_ca197a64-193b-4f1b-863a-fdf93d9cc0ee_totalLabel_en-US" xlink:label="lab_us-gaap_NoninterestIncome" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total noninterest income</link:label>
    <link:label id="lab_us-gaap_NoninterestIncome_label_en-US" xlink:label="lab_us-gaap_NoninterestIncome" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noninterest Income</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncome" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoninterestIncome"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoninterestIncome" xlink:to="lab_us-gaap_NoninterestIncome" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ForeclosedAssetMember_89a51078-f430-4e97-8259-8f9005228211_terseLabel_en-US" xlink:label="lab_isba_ForeclosedAssetMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreclosed Asset</link:label>
    <link:label id="lab_isba_ForeclosedAssetMember_label_en-US" xlink:label="lab_isba_ForeclosedAssetMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Foreclosed Asset [Member]</link:label>
    <link:label id="lab_isba_ForeclosedAssetMember_documentation_en-US" xlink:label="lab_isba_ForeclosedAssetMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Foreclosed Asset [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ForeclosedAssetMember" xlink:href="isba-20231231.xsd#isba_ForeclosedAssetMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ForeclosedAssetMember" xlink:to="lab_isba_ForeclosedAssetMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_77d0589e-b588-4fd7-9758-79eebbbd0b5d_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Summary of deferred tax assets and liabilities</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Deferred Tax Assets and Liabilities [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CounterpartyNameAxis_e729f519-5656-461a-814a-b7e8e792a8d6_terseLabel_en-US" xlink:label="lab_srt_CounterpartyNameAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Counterparty Name [Axis]</link:label>
    <link:label id="lab_srt_CounterpartyNameAxis_label_en-US" xlink:label="lab_srt_CounterpartyNameAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Counterparty Name [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CounterpartyNameAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CounterpartyNameAxis" xlink:to="lab_srt_CounterpartyNameAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_b1949ef7-1ce8-41b4-8af9-9c7b66b72707_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Related Party Transactions, by Related Party [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Related Party Transactions, by Related Party [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_2f282cfc-ba55-451e-9100-e8006be8c515_verboseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year 1</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Asset, Expected Amortization, Year One</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InternalCreditAssessmentDomain_64c31e44-3a97-48b9-98c4-84b6dc1fc219_terseLabel_en-US" xlink:label="lab_us-gaap_InternalCreditAssessmentDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Internal Credit Assessment [Domain]</link:label>
    <link:label id="lab_us-gaap_InternalCreditAssessmentDomain_label_en-US" xlink:label="lab_us-gaap_InternalCreditAssessmentDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Internal Credit Assessment [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain" xlink:to="lab_us-gaap_InternalCreditAssessmentDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonStockSharesOutstanding_1454be34-43b3-42fe-b0ea-0ee9cb34d80c_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares outstanding</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesOutstanding_fe74f007-8e86-4eba-9082-28cc4fea4278_periodStartLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Beginning balances, shares</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesOutstanding_6acc90e0-adf3-43b2-a905-f726d7af1082_periodEndLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Ending balances, shares</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesOutstanding_label_en-US" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares, Outstanding</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesOutstanding" xlink:to="lab_us-gaap_CommonStockSharesOutstanding" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherInvestments_76d85e21-ce1b-407f-8cbc-8e3a23a8ab85_verboseLabel_en-US" xlink:label="lab_us-gaap_OtherInvestments" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_OtherInvestments_label_en-US" xlink:label="lab_us-gaap_OtherInvestments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Investments</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherInvestments" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherInvestments"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherInvestments" xlink:to="lab_us-gaap_OtherInvestments" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanInterestCost_14ec088d-9ab4-43bd-a2dd-89ae7ebdda9a_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanInterestCost" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest cost</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanInterestCost_ab0f8972-0249-4b24-8e86-bdcacd128783_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanInterestCost" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interest cost on benefit obligation</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanInterestCost_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanInterestCost" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Interest Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanInterestCost" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanInterestCost"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanInterestCost" xlink:to="lab_us-gaap_DefinedBenefitPlanInterestCost" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesAfterYearFive_30b0e85f-5bb9-4e0f-b2b0-bc0e2a506689_verboseLabel_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesAfterYearFive" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Thereafter</link:label>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesAfterYearFive_label_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesAfterYearFive" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Time Deposit Maturities, after Year Five</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesAfterYearFive" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TimeDepositMaturitiesAfterYearFive"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimeDepositMaturitiesAfterYearFive" xlink:to="lab_us-gaap_TimeDepositMaturitiesAfterYearFive" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherIncomeAndExpensesAbstract_6f22a682-0439-4034-9df2-3eefa0fb09db_terseLabel_en-US" xlink:label="lab_us-gaap_OtherIncomeAndExpensesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Income and Expenses [Abstract]</link:label>
    <link:label id="lab_us-gaap_OtherIncomeAndExpensesAbstract_label_en-US" xlink:label="lab_us-gaap_OtherIncomeAndExpensesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Income and Expenses [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherIncomeAndExpensesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherIncomeAndExpensesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherIncomeAndExpensesAbstract" xlink:to="lab_us-gaap_OtherIncomeAndExpensesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ConcentrationRiskCreditRisk_a8c8781f-c208-49c1-8351-a322b1de9977_verboseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskCreditRisk" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">SIGNIFICANT GROUP CONCENTRATIONS OF CREDIT RISK</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskCreditRisk_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskCreditRisk" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskCreditRisk" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskCreditRisk"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskCreditRisk" xlink:to="lab_us-gaap_ConcentrationRiskCreditRisk" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StockholdersEquityOther_2d63ad91-e2c4-4952-8246-f8a45b5c3b7e_terseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityOther" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stockholders' Equity, Other</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityOther_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityOther" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity, Other</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityOther" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquityOther"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityOther" xlink:to="lab_us-gaap_StockholdersEquityOther" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_AuditorLocation_f3269076-a753-4680-99b0-f5b6cd79f474_terseLabel_en-US" xlink:label="lab_dei_AuditorLocation" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Auditor Location</link:label>
    <link:label id="lab_dei_AuditorLocation_label_en-US" xlink:label="lab_dei_AuditorLocation" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Auditor Location</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AuditorLocation" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_AuditorLocation"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_AuditorLocation" xlink:to="lab_dei_AuditorLocation" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems_747892bc-296f-4267-88cd-b0fb859477f3_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Disclosure [Line Items]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan Disclosure [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:to="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition_09a7695f-caa5-4abc-864b-5c8b3570e7a5_terseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">APIC, Share-based Payment Arrangement, Other, Increase for Cost Recognition</link:label>
    <link:label id="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition_label_en-US" xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">APIC, Share-Based Payment Arrangement, Other, Increase for Cost Recognition</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition" xlink:to="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationOtherLongtermIncentivePlansRequisiteServicePeriodRecognition" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward_83e2e46c-ab0b-4eab-85d7-8534af5362b8_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Change in plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward" xlink:to="lab_us-gaap_DefinedBenefitPlanChangeInFairValueOfPlanAssetsRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedContributionPlanDisclosureLineItems_70d6fcba-715e-419b-b401-a28e227654df_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanDisclosureLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan Disclosure [Line Items]</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanDisclosureLineItems_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanDisclosureLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan Disclosure [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanDisclosureLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedContributionPlanDisclosureLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanDisclosureLineItems" xlink:to="lab_us-gaap_DefinedContributionPlanDisclosureLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_MarketingExpense_f97a5998-5aaa-44f2-9982-f638aea584f2_terseLabel_en-US" xlink:label="lab_us-gaap_MarketingExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Marketing Expense</link:label>
    <link:label id="lab_us-gaap_MarketingExpense_label_en-US" xlink:label="lab_us-gaap_MarketingExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Marketing Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketingExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MarketingExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MarketingExpense" xlink:to="lab_us-gaap_MarketingExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_31491841-1f8b-4913-ab3c-1dad8cce0477_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net cash provided by (used in) investing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableRelatedParties_08d01e87-c165-4352-a812-74d02ff9087a_periodStartLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableRelatedParties" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Balance, January 1</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableRelatedParties_ca17b00e-5206-4f83-9862-b209f24caed7_periodEndLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableRelatedParties" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Balance, December 31</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableRelatedParties_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableRelatedParties" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Related Parties</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableRelatedParties" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableRelatedParties"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableRelatedParties" xlink:to="lab_us-gaap_LoansAndLeasesReceivableRelatedParties" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember_fa3b40f8-cec4-47cf-8957-8de2de0cd9dc_terseLabel_en-US" xlink:label="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Securities Sold under Agreements to Repurchase [Member]</link:label>
    <link:label id="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember_label_en-US" xlink:label="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Securities Sold under Agreements to Repurchase [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember" xlink:to="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue_f13df92a-ce58-46c3-bd95-fa4759c5d230_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProfessionalFees_0bcada2a-3501-44ec-aee5-9ccfc27cab93_verboseLabel_en-US" xlink:label="lab_us-gaap_ProfessionalFees" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Professional Fees, Audit, Consulting, &amp; Legal</link:label>
    <link:label id="lab_us-gaap_ProfessionalFees_7a0b80d3-e600-4ac6-9f89-ca365c7bc15d_terseLabel_en-US" xlink:label="lab_us-gaap_ProfessionalFees" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Professional Fees</link:label>
    <link:label id="lab_us-gaap_ProfessionalFees_label_en-US" xlink:label="lab_us-gaap_ProfessionalFees" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Professional Fees</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfessionalFees" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProfessionalFees"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProfessionalFees" xlink:to="lab_us-gaap_ProfessionalFees" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentAxis_dfa492c2-e34c-4141-8ed5-e0ff7daebdf5_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument [Axis]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentAxis_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentAxis" xlink:to="lab_us-gaap_DebtInstrumentAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions_376c43b8-2f24-463b-b6d7-c6c2aaca00b4_totalLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PercentageOfReportableSegmentAssetsAndOperatingResults_74043356-bff9-4fb2-9bfd-c7a53ce9e89d_verboseLabel_en-US" xlink:label="lab_isba_PercentageOfReportableSegmentAssetsAndOperatingResults" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Percentage of reportable segments total assets and operating results, or more</link:label>
    <link:label id="lab_isba_PercentageOfReportableSegmentAssetsAndOperatingResults_label_en-US" xlink:label="lab_isba_PercentageOfReportableSegmentAssetsAndOperatingResults" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Percentage Of Reportable Segment, Assets And Operating Results</link:label>
    <link:label id="lab_isba_PercentageOfReportableSegmentAssetsAndOperatingResults_documentation_en-US" xlink:label="lab_isba_PercentageOfReportableSegmentAssetsAndOperatingResults" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Percentage Of Reportable Segment, Assets And Operating Results</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PercentageOfReportableSegmentAssetsAndOperatingResults" xlink:href="isba-20231231.xsd#isba_PercentageOfReportableSegmentAssetsAndOperatingResults"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PercentageOfReportableSegmentAssetsAndOperatingResults" xlink:to="lab_isba_PercentageOfReportableSegmentAssetsAndOperatingResults" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesAbstract_72688316-683f-4f58-9fb3-db4e5ca1da74_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax liabilities</link:label>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesAbstract_label_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Gross [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxLiabilitiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesAbstract" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets_c1e21c65-2c2b-4833-81bf-33c99809ff6a_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio</link:label>
    <link:label id="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets_label_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Leverage Capital Ratio, Well Capitalized, Minimum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets" xlink:to="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CreditFacilityAxis_3e2be12c-d6a7-4ed5-a439-74411e291625_terseLabel_en-US" xlink:label="lab_us-gaap_CreditFacilityAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit Facility [Axis]</link:label>
    <link:label id="lab_us-gaap_CreditFacilityAxis_label_en-US" xlink:label="lab_us-gaap_CreditFacilityAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Facility [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CreditFacilityAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CreditFacilityAxis" xlink:to="lab_us-gaap_CreditFacilityAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax_aeda5f11-4356-4718-a2ae-d5b94a155e81_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Liabilities_e697f06b-ae10-4746-bc71-8d13867993c0_totalLabel_en-US" xlink:label="lab_us-gaap_Liabilities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total liabilities</link:label>
    <link:label id="lab_us-gaap_Liabilities_label_en-US" xlink:label="lab_us-gaap_Liabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Liabilities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Liabilities" xlink:to="lab_us-gaap_Liabilities" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod_1b7ab071-eaf9-48dd-a2b4-f09c6bbf8a8c_terseLabel_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Granted</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod_label_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Granted in Period</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod_documentation_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Granted in Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod" xlink:href="isba-20231231.xsd#isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod" xlink:to="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGrantedInPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear_420b9e6e-c78a-4223-8a28-04f295d76e98_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear" xlink:to="lab_us-gaap_FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember_59729709-b7b1-4b1e-9c32-ec1e61585d25_terseLabel_en-US" xlink:label="lab_srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cumulative Effect, Period of Adoption, Adjusted Balance</link:label>
    <link:label id="lab_srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember_label_en-US" xlink:label="lab_srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cumulative Effect, Period of Adoption, Adjusted Balance [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember" xlink:to="lab_srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesTableTextBlock_8ccc7ae1-4da1-47bc-a7db-23392af62f39_terseLabel_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal home loan bank, advances</link:label>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesTableTextBlock_label_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankAdvancesTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalHomeLoanBankAdvancesTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalHomeLoanBankAdvancesTableTextBlock" xlink:to="lab_us-gaap_FederalHomeLoanBankAdvancesTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueMeasurementFrequencyDomain_b32485a3-7163-4ca4-9261-668b29954b95_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueMeasurementFrequencyDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value, Measurement Frequency [Domain]</link:label>
    <link:label id="lab_us-gaap_FairValueMeasurementFrequencyDomain_label_en-US" xlink:label="lab_us-gaap_FairValueMeasurementFrequencyDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Measurement Frequency [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain" xlink:to="lab_us-gaap_FairValueMeasurementFrequencyDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_f0b0d3bf-b06c-4d16-a566-dcdcf05f59c3_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Premises and Equipment</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_TitleOfIndividualAxis_6c827052-d0e8-4d2a-9106-db4bb1fb85fc_terseLabel_en-US" xlink:label="lab_srt_TitleOfIndividualAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Title of Individual [Axis]</link:label>
    <link:label id="lab_srt_TitleOfIndividualAxis_label_en-US" xlink:label="lab_srt_TitleOfIndividualAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Title of Individual [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualAxis" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_TitleOfIndividualAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_TitleOfIndividualAxis" xlink:to="lab_srt_TitleOfIndividualAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_5320c697-858c-4687-bf4c-981a6b72d540_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of Financing Receivable [Axis]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_de8d72d6-ceea-4236-9ec2-46a4bcb8e6b3_verboseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Class of Financing Receivable</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_17cc7df5-23e5-44e4-961c-9b29e14aa258_netLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xlink:role="http://www.xbrl.org/2009/role/netLabel" xlink:type="resource" xml:lang="en-US">Class of Financing Receivable [Axis]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Financing Receivable [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xlink:to="lab_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary_21eff3fa-23d1-4036-ac95-8980f56a0d5f_terseLabel_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Award as a percentage of salary</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary_label_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Employee Annual Salary</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary_documentation_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Employee Annual Salary</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary" xlink:href="isba-20231231.xsd#isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary" xlink:to="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfEmployeeAnnualSalary" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_29ed52a4-db50-4d70-9ddf-41feea6d93a2_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Domain]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-Lived Tangible Asset [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract_40eeb2e0-d0cb-4a26-8d52-926ec27bd4b7_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Actuarial weighted average assumptions used in determining the net periodic pension costs</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" xlink:to="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_MarketableSecuritiesPolicy_4b0df525-1f19-4502-a483-e0ca010c1871_verboseLabel_en-US" xlink:label="lab_us-gaap_MarketableSecuritiesPolicy" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities</link:label>
    <link:label id="lab_us-gaap_MarketableSecuritiesPolicy_label_en-US" xlink:label="lab_us-gaap_MarketableSecuritiesPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Marketable Securities, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MarketableSecuritiesPolicy" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MarketableSecuritiesPolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MarketableSecuritiesPolicy" xlink:to="lab_us-gaap_MarketableSecuritiesPolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_17c597c3-277e-451b-8bfb-bfb2684041bf_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year Two</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Two</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_AffiliatedEntityMember_26151aab-e138-483c-941d-66fcda53a76a_terseLabel_en-US" xlink:label="lab_srt_AffiliatedEntityMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Affiliated Entity [Member]</link:label>
    <link:label id="lab_srt_AffiliatedEntityMember_label_en-US" xlink:label="lab_srt_AffiliatedEntityMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Affiliated Entity [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_AffiliatedEntityMember" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_AffiliatedEntityMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_AffiliatedEntityMember" xlink:to="lab_srt_AffiliatedEntityMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax_5e9b4a90-cc93-4be7-bd64-0e9f3b09232b_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net unrealized gains (losses)</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_d1ac5f36-7eb3-4bd9-aaea-4215b9753da8_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestAndFeeIncomeLoansAndLeases_138f4b2f-5666-434b-aeaa-12585e634946_verboseLabel_en-US" xlink:label="lab_us-gaap_InterestAndFeeIncomeLoansAndLeases" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Loans, including fees</link:label>
    <link:label id="lab_us-gaap_InterestAndFeeIncomeLoansAndLeases_label_en-US" xlink:label="lab_us-gaap_InterestAndFeeIncomeLoansAndLeases" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest and Fee Income, Loans and Leases</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndFeeIncomeLoansAndLeases" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestAndFeeIncomeLoansAndLeases"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestAndFeeIncomeLoansAndLeases" xlink:to="lab_us-gaap_InterestAndFeeIncomeLoansAndLeases" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialAndCommercialRealEstatePortfolioSegmentMember_7cdada2e-f0a6-418a-b435-57d4769a2977_terseLabel_en-US" xlink:label="lab_isba_CommercialAndCommercialRealEstatePortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial and Commercial Real Estate Portfolio Segment</link:label>
    <link:label id="lab_isba_CommercialAndCommercialRealEstatePortfolioSegmentMember_label_en-US" xlink:label="lab_isba_CommercialAndCommercialRealEstatePortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial and Commercial Real Estate Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialAndCommercialRealEstatePortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_CommercialAndCommercialRealEstatePortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial and Commercial Real Estate Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialAndCommercialRealEstatePortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_CommercialAndCommercialRealEstatePortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialAndCommercialRealEstatePortfolioSegmentMember" xlink:to="lab_isba_CommercialAndCommercialRealEstatePortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ConsumerPortfolioSegmentMember_dd532bfb-293a-4cb6-b6ec-426f1828d7b3_terseLabel_en-US" xlink:label="lab_us-gaap_ConsumerPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total consumer [Member]</link:label>
    <link:label id="lab_us-gaap_ConsumerPortfolioSegmentMember_8b108c9d-61c3-4fc8-8f25-2797026596ca_verboseLabel_en-US" xlink:label="lab_us-gaap_ConsumerPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Consumer [Member]</link:label>
    <link:label id="lab_us-gaap_ConsumerPortfolioSegmentMember_label_en-US" xlink:label="lab_us-gaap_ConsumerPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consumer Portfolio Segment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerPortfolioSegmentMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConsumerPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConsumerPortfolioSegmentMember" xlink:to="lab_us-gaap_ConsumerPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NoninterestExpenseAbstract_6ada902c-108f-4e3c-bfc2-ed3078b6525f_verboseLabel_en-US" xlink:label="lab_us-gaap_NoninterestExpenseAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Noninterest expenses</link:label>
    <link:label id="lab_us-gaap_NoninterestExpenseAbstract_label_en-US" xlink:label="lab_us-gaap_NoninterestExpenseAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noninterest Expense [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpenseAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoninterestExpenseAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoninterestExpenseAbstract" xlink:to="lab_us-gaap_NoninterestExpenseAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfShortTermDebtTextBlock_713d3987-d446-4a30-b99a-e40054fca3be_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfShortTermDebtTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of short term borrowings</link:label>
    <link:label id="lab_us-gaap_ScheduleOfShortTermDebtTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfShortTermDebtTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Short-Term Debt [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShortTermDebtTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfShortTermDebtTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfShortTermDebtTextBlock" xlink:to="lab_us-gaap_ScheduleOfShortTermDebtTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_96e3655b-d572-4ec0-a1ca-d37bafccaf87_verboseLabel_en-US" xlink:label="lab_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Investments in subsidiaries</link:label>
    <link:label id="lab_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_label_en-US" xlink:label="lab_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:to="lab_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage_85fa4737-dfa5-4222-ae8d-bc8b0969c2b5_terseLabel_en-US" xlink:label="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage</link:label>
    <link:label id="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage_label_en-US" xlink:label="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage</link:label>
    <link:label id="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage_documentation_en-US" xlink:label="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage" xlink:href="isba-20231231.xsd#isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage" xlink:to="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueWeightedAverage" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod_bee5e29a-bbd3-40de-9418-87cb6d0afb35_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Losses, Effect of Change in Method</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Losses, Effect of Change in Method</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod" xlink:to="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_0f0459fd-10b2-46d9-9e68-91d5c81b4b29_negatedLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net periodic cost for the year</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_67660bf0-c99d-4475-99e3-4dd8ccdc08b8_negatedTotalLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="resource" xml:lang="en-US">Net periodic cost for the year</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Net Periodic Benefit Cost (Credit)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:to="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember_4de6d48e-bf20-4c9b-ae55-4efa4c022ff1_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]</link:label>
    <link:label id="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember_label_en-US" xlink:label="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:to="lab_us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ExtendedMaturityAndInterestRateReductionMember_781e09aa-40da-476b-97c5-9b75d6e4bf76_terseLabel_en-US" xlink:label="lab_us-gaap_ExtendedMaturityAndInterestRateReductionMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Extended Maturity and Interest Rate Reduction</link:label>
    <link:label id="lab_us-gaap_ExtendedMaturityAndInterestRateReductionMember_label_en-US" xlink:label="lab_us-gaap_ExtendedMaturityAndInterestRateReductionMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Extended Maturity and Interest Rate Reduction [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExtendedMaturityAndInterestRateReductionMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ExtendedMaturityAndInterestRateReductionMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ExtendedMaturityAndInterestRateReductionMember" xlink:to="lab_us-gaap_ExtendedMaturityAndInterestRateReductionMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SupplementalCashFlowInformationAbstract_51a4e59f-0c61-4d87-999e-adf4d4cb356c_verboseLabel_en-US" xlink:label="lab_us-gaap_SupplementalCashFlowInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">SUPPLEMENTAL CASH FLOWS INFORMATION:</link:label>
    <link:label id="lab_us-gaap_SupplementalCashFlowInformationAbstract_label_en-US" xlink:label="lab_us-gaap_SupplementalCashFlowInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Supplemental Cash Flow Information [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplementalCashFlowInformationAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SupplementalCashFlowInformationAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SupplementalCashFlowInformationAbstract" xlink:to="lab_us-gaap_SupplementalCashFlowInformationAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_be2a5379-9632-4164-bf50-6735bea3d02e_verboseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Credit quality indicators by year of origination</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable Credit Quality Indicators [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock" xlink:to="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RetirementPlanNameDomain_cd3e68e8-c7f3-4cc2-b640-3db8b9f912df_terseLabel_en-US" xlink:label="lab_us-gaap_RetirementPlanNameDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement Plan Name [Domain]</link:label>
    <link:label id="lab_us-gaap_RetirementPlanNameDomain_label_en-US" xlink:label="lab_us-gaap_RetirementPlanNameDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Plan Name [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetirementPlanNameDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanNameDomain" xlink:to="lab_us-gaap_RetirementPlanNameDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLosses_b2cf3847-acac-4e4f-94f6-e863c6744f4b_verboseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLosses" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Allowance for loan losses, Ending Balance</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLosses_26f3f287-db5b-40a4-a839-1586ce52bd4e_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLosses" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Allowance for loan losses, Beginning Balance</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLosses_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLosses" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Loss</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLosses" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableAllowanceForCreditLosses"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLosses" xlink:to="lab_us-gaap_FinancingReceivableAllowanceForCreditLosses" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherLiabilities_5a0a6d71-8570-4114-90d8-6c3a0140ca01_verboseLabel_en-US" xlink:label="lab_us-gaap_OtherLiabilities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other liabilities</link:label>
    <link:label id="lab_us-gaap_OtherLiabilities_label_en-US" xlink:label="lab_us-gaap_OtherLiabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherLiabilities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLiabilities" xlink:to="lab_us-gaap_OtherLiabilities" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShortTermDebtTypeDomain_6dbe2bab-33fc-4cec-bc6e-b349a1565f8f_terseLabel_en-US" xlink:label="lab_us-gaap_ShortTermDebtTypeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Short-term Debt, Type [Domain]</link:label>
    <link:label id="lab_us-gaap_ShortTermDebtTypeDomain_label_en-US" xlink:label="lab_us-gaap_ShortTermDebtTypeDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Debt, Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermDebtTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShortTermDebtTypeDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShortTermDebtTypeDomain" xlink:to="lab_us-gaap_ShortTermDebtTypeDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets_fc52c6e4-763b-4bb8-8431-38e0f17a5b20_verboseLabel_en-US" xlink:label="lab_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Corporation recorded servicing fee revenue</link:label>
    <link:label id="lab_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets_label_en-US" xlink:label="lab_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Contractually Specified Servicing Fee, Late Fee, and Ancillary Fee Earned in Exchange for Servicing Financial Asset</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets" xlink:to="lab_us-gaap_ContractuallySpecifiedServicingFeesLateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EarningsPerSharePolicyTextBlock_3061dca8-1878-4749-867a-e2471e220393_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerSharePolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Earnings Per Share</link:label>
    <link:label id="lab_us-gaap_EarningsPerSharePolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_EarningsPerSharePolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerSharePolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EarningsPerSharePolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerSharePolicyTextBlock" xlink:to="lab_us-gaap_EarningsPerSharePolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_e6350e60-8fb5-44a4-abfc-5cf08af6399a_verboseLabel_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Goodwill and Other Intangible Assets</link:label>
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill and Intangible Assets Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock" xlink:to="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember_c8e508b5-c91b-43b4-8332-8d57b264d0a5_terseLabel_en-US" xlink:label="lab_isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, 1-4 Family Investor, Portfolio Segment</link:label>
    <link:label id="lab_isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, 1-4 Family Investor, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, 1-4 Family Investor, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember" xlink:to="lab_isba_CommercialRealEstate14FamilyInvestorPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_c0b6eb40-2a8c-49f6-97eb-cc6b990cae44_terseLabel_en-US" xlink:label="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pending Accounting Standards Updates</link:label>
    <link:label id="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_label_en-US" xlink:label="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Standards Update and Change in Accounting Principle [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:to="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_beabbf2d-15dc-48a9-b749-921dd3f97058_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of the components of accumulated other comprehensive income</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems_36291c9d-0c4a-4a6b-8698-d8401b6b3d08_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]</link:label>
    <link:label id="lab_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems_label_en-US" xlink:label="lab_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Share-Based Payments [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="lab_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_fa18f3b9-d002-454c-b6b8-7b462ad710ac_terseLabel_en-US" xlink:label="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Postretirement Benefits Plan [Member]</link:label>
    <link:label id="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember_label_en-US" xlink:label="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Postretirement Benefits Plan [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:to="lab_us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_fc48631e-7138-41a3-b3d6-19617986ed6b_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net cash provided by (used in) operating activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_a2031b6d-5637-4b17-aa0e-4820955fddc8_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net cash provided by (used in) operating activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ForwardContractsMember_8f5cd661-4e2b-42da-80a4-cda31dfedc86_terseLabel_en-US" xlink:label="lab_us-gaap_ForwardContractsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Forward Contracts [Member]</link:label>
    <link:label id="lab_us-gaap_ForwardContractsMember_label_en-US" xlink:label="lab_us-gaap_ForwardContractsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Forward Contracts [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForwardContractsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ForwardContractsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ForwardContractsMember" xlink:to="lab_us-gaap_ForwardContractsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_42296758-b76f-4205-82be-6cf615dfde17_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of estimated amortization expense associated with identifiable intangibles</link:label>
    <link:label id="lab_us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock" xlink:to="lab_us-gaap_ScheduleofFiniteLivedIntangibleAssetsFutureAmortizationExpenseTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment_15432b2d-3f5d-4673-87b8-4d2b9ace6f15_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Collectively Evaluated for Impairment</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Collectively Evaluated for Impairment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment" xlink:to="lab_us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount_503b1c51-d8be-453b-aeb7-6cb1ac9a3241_negatedTotalLabel_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="resource" xml:lang="en-US">Total effect of nontaxable income</link:label>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount_label_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Exempt Income And Tax Credits, Amount</link:label>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount_documentation_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Exempt Income And Tax Credits, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount" xlink:href="isba-20231231.xsd#isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount" xlink:to="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeAndTaxCreditsAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsGrossAbstract_dd18c874-74ca-465f-af4a-b0427ec6eaa1_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsGrossAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred tax assets</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsGrossAbstract_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsGrossAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Gross [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsGrossAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsGrossAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsGrossAbstract" xlink:to="lab_us-gaap_DeferredTaxAssetsGrossAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_723b9da7-2f15-497d-88cf-c92f99f041d3_terseLabel_en-US" xlink:label="lab_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]</link:label>
    <link:label id="lab_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems_label_en-US" xlink:label="lab_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems" xlink:to="lab_us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FurnitureAndFixturesMember_b7d0da25-3385-4b70-b2ce-f378b896537b_verboseLabel_en-US" xlink:label="lab_us-gaap_FurnitureAndFixturesMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Furniture and equipment [Member]</link:label>
    <link:label id="lab_us-gaap_FurnitureAndFixturesMember_3bf35604-522e-4f58-ab88-deecf92c44f8_terseLabel_en-US" xlink:label="lab_us-gaap_FurnitureAndFixturesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Furniture and Fixtures [Member]</link:label>
    <link:label id="lab_us-gaap_FurnitureAndFixturesMember_label_en-US" xlink:label="lab_us-gaap_FurnitureAndFixturesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Furniture and Fixtures [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FurnitureAndFixturesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FurnitureAndFixturesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FurnitureAndFixturesMember" xlink:to="lab_us-gaap_FurnitureAndFixturesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis_15d5515f-0a23-4512-b56e-82daf65d0d5a_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Maturing, Due in One Year or Less</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Amortized Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_9974fbcb-3985-415b-9634-dd545a5504a7_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Troubled Debt Restructurings [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Modified [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable" xlink:to="lab_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_Donationsandcommunityrelations_c77e11d0-9fd6-4f2a-8215-aad9e7205f15_terseLabel_en-US" xlink:label="lab_isba_Donationsandcommunityrelations" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Donations and community relations</link:label>
    <link:label id="lab_isba_Donationsandcommunityrelations_label_en-US" xlink:label="lab_isba_Donationsandcommunityrelations" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Donations and community relations</link:label>
    <link:label id="lab_isba_Donationsandcommunityrelations_documentation_en-US" xlink:label="lab_isba_Donationsandcommunityrelations" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Donations and community relations</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_Donationsandcommunityrelations" xlink:href="isba-20231231.xsd#isba_Donationsandcommunityrelations"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_Donationsandcommunityrelations" xlink:to="lab_isba_Donationsandcommunityrelations" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily_2f587a74-f6e4-44d7-b942-a09fd3a5edf0_verboseLabel_en-US" xlink:label="lab_isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Corporation self-funded medical plan</link:label>
    <link:label id="lab_isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily_label_en-US" xlink:label="lab_isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Self Funded Medical Plan, Maximum Amount Paid Per Family</link:label>
    <link:label id="lab_isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily_documentation_en-US" xlink:label="lab_isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Self Funded Medical Plan, Maximum Amount Paid Per Family</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily" xlink:href="isba-20231231.xsd#isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily" xlink:to="lab_isba_SelfFundedMedicalPlanMaximumAmountPaidPerFamily" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_48ce881e-d9ad-45d4-992d-7f8c0045dc1e_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ConsumerLoanMember_2598dffd-d6a9-4435-8f2c-0e68d2561484_terseLabel_en-US" xlink:label="lab_us-gaap_ConsumerLoanMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consumer Loan</link:label>
    <link:label id="lab_us-gaap_ConsumerLoanMember_label_en-US" xlink:label="lab_us-gaap_ConsumerLoanMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consumer Loan [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerLoanMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConsumerLoanMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConsumerLoanMember" xlink:to="lab_us-gaap_ConsumerLoanMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ChangesInProjectedBenefitObligationsFairValueOfPlanAssetsAndFundedStatusOfPlanTableTextBlock_3f9445d3-ca01-4f1e-b2bf-59a4a456866b_terseLabel_en-US" xlink:label="lab_us-gaap_ChangesInProjectedBenefitObligationsFairValueOfPlanAssetsAndFundedStatusOfPlanTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in the projected benefit obligation, plan assets and Accrued pension benefit costs</link:label>
    <link:label id="lab_us-gaap_ChangesInProjectedBenefitObligationsFairValueOfPlanAssetsAndFundedStatusOfPlanTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ChangesInProjectedBenefitObligationsFairValueOfPlanAssetsAndFundedStatusOfPlanTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Changes in Projected Benefit Obligations, Fair Value of Plan Assets, and Funded Status of Plan [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ChangesInProjectedBenefitObligationsFairValueOfPlanAssetsAndFundedStatusOfPlanTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ChangesInProjectedBenefitObligationsFairValueOfPlanAssetsAndFundedStatusOfPlanTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ChangesInProjectedBenefitObligationsFairValueOfPlanAssetsAndFundedStatusOfPlanTableTextBlock" xlink:to="lab_us-gaap_ChangesInProjectedBenefitObligationsFairValueOfPlanAssetsAndFundedStatusOfPlanTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_ScheduleOfCondensedCashFlowStatementTableTextBlock_f20be7c4-25e2-4aae-8875-a150e5866305_verboseLabel_en-US" xlink:label="lab_srt_ScheduleOfCondensedCashFlowStatementTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interim Condensed Statements of Cash Flows</link:label>
    <link:label id="lab_srt_ScheduleOfCondensedCashFlowStatementTableTextBlock_label_en-US" xlink:label="lab_srt_ScheduleOfCondensedCashFlowStatementTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Cash Flow Statement [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfCondensedCashFlowStatementTableTextBlock" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ScheduleOfCondensedCashFlowStatementTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ScheduleOfCondensedCashFlowStatementTableTextBlock" xlink:to="lab_srt_ScheduleOfCondensedCashFlowStatementTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ServicingAssetAtFairValueAmount_8575d30d-a4e9-40dc-92da-16e6e277413b_verboseLabel_en-US" xlink:label="lab_us-gaap_ServicingAssetAtFairValueAmount" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">OMSR</link:label>
    <link:label id="lab_us-gaap_ServicingAssetAtFairValueAmount_label_en-US" xlink:label="lab_us-gaap_ServicingAssetAtFairValueAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Servicing Asset at Fair Value, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetAtFairValueAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ServicingAssetAtFairValueAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ServicingAssetAtFairValueAmount" xlink:to="lab_us-gaap_ServicingAssetAtFairValueAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentAdviceMember_91dd0d5b-c3af-4132-afa7-9d4e60852779_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentAdviceMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investment Advice [Member]</link:label>
    <link:label id="lab_us-gaap_InvestmentAdviceMember_label_en-US" xlink:label="lab_us-gaap_InvestmentAdviceMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment Advice [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentAdviceMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentAdviceMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentAdviceMember" xlink:to="lab_us-gaap_InvestmentAdviceMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing_2a8e010f-d395-41a9-8cf7-55562f936f4a_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivables, 90 Days or More Past Due, Still Accruing</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, 90 Days or More Past Due, Still Accruing</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing" xlink:to="lab_us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialAndIndustrialSecuredPortfolioSegmentMember_97c3f153-2915-4268-8f7e-9b717903a028_terseLabel_en-US" xlink:label="lab_isba_CommercialAndIndustrialSecuredPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial and Industrial, Secured, Portfolio Segment</link:label>
    <link:label id="lab_isba_CommercialAndIndustrialSecuredPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_CommercialAndIndustrialSecuredPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial and Industrial, Secured, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialAndIndustrialSecuredPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_CommercialAndIndustrialSecuredPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial and Industrial, Secured, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialAndIndustrialSecuredPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_CommercialAndIndustrialSecuredPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialAndIndustrialSecuredPortfolioSegmentMember" xlink:to="lab_isba_CommercialAndIndustrialSecuredPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_OtherNoninterestExpenseMiscellaneous_4473703b-49e9-4b4a-b2c1-dc62e30f31cc_terseLabel_en-US" xlink:label="lab_isba_OtherNoninterestExpenseMiscellaneous" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">All other</link:label>
    <link:label id="lab_isba_OtherNoninterestExpenseMiscellaneous_label_en-US" xlink:label="lab_isba_OtherNoninterestExpenseMiscellaneous" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Noninterest Expense Miscellaneous</link:label>
    <link:label id="lab_isba_OtherNoninterestExpenseMiscellaneous_documentation_en-US" xlink:label="lab_isba_OtherNoninterestExpenseMiscellaneous" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Noninterest Expense Miscellaneous</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_OtherNoninterestExpenseMiscellaneous" xlink:href="isba-20231231.xsd#isba_OtherNoninterestExpenseMiscellaneous"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_OtherNoninterestExpenseMiscellaneous" xlink:to="lab_isba_OtherNoninterestExpenseMiscellaneous" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RetirementPlanNameAxis_bbca3cba-4d21-4164-9f26-3aa91abcffc0_terseLabel_en-US" xlink:label="lab_us-gaap_RetirementPlanNameAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement Plan Name [Axis]</link:label>
    <link:label id="lab_us-gaap_RetirementPlanNameAxis_label_en-US" xlink:label="lab_us-gaap_RetirementPlanNameAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Plan Name [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanNameAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetirementPlanNameAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanNameAxis" xlink:to="lab_us-gaap_RetirementPlanNameAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_af9c7fb9-d328-410a-8284-95ef69a0e937_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Axis]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-Lived Tangible Asset [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableYearOneOriginatedCurrentFiscalYearWriteoff_b67ccccc-4af5-471f-8eeb-3fb03a473d7a_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearOneOriginatedCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableYearOneOriginatedCurrentFiscalYearWriteoff_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearOneOriginatedCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableYearOneOriginatedCurrentFiscalYearWriteoff" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableYearOneOriginatedCurrentFiscalYearWriteoff"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableYearOneOriginatedCurrentFiscalYearWriteoff" xlink:to="lab_us-gaap_FinancingReceivableYearOneOriginatedCurrentFiscalYearWriteoff" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstract_b69534c8-a977-4c96-9e67-c8ac745dd214_terseLabel_en-US" xlink:label="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">New Accounting Pronouncements and Changes in Accounting Principles [Abstract]</link:label>
    <link:label id="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstract_label_en-US" xlink:label="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Standards Update and Change in Accounting Principle [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstract" xlink:to="lab_us-gaap_NewAccountingPronouncementsAndChangesInAccountingPrinciplesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityEmergingGrowthCompany_7ebe20c2-93eb-4ae1-824a-515699d88740_terseLabel_en-US" xlink:label="lab_dei_EntityEmergingGrowthCompany" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Emerging Growth Company</link:label>
    <link:label id="lab_dei_EntityEmergingGrowthCompany_label_en-US" xlink:label="lab_dei_EntityEmergingGrowthCompany" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Emerging Growth Company</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityEmergingGrowthCompany" xlink:to="lab_dei_EntityEmergingGrowthCompany" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ATMandDebitCardExpense_eba3eaf0-c62d-4f65-83e2-c1be32025b50_terseLabel_en-US" xlink:label="lab_isba_ATMandDebitCardExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">ATM and Debit Card Expense</link:label>
    <link:label id="lab_isba_ATMandDebitCardExpense_label_en-US" xlink:label="lab_isba_ATMandDebitCardExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">ATM and Debit Card Expense</link:label>
    <link:label id="lab_isba_ATMandDebitCardExpense_documentation_en-US" xlink:label="lab_isba_ATMandDebitCardExpense" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">ATM and Debit Card Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ATMandDebitCardExpense" xlink:href="isba-20231231.xsd#isba_ATMandDebitCardExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ATMandDebitCardExpense" xlink:to="lab_isba_ATMandDebitCardExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff_122382e9-3e05-4db6-9976-1da9c6e30413_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff" xlink:to="lab_us-gaap_FinancingReceivableYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommonStockHeldinTrustShares_19c2f44a-532c-4142-943e-42836e8896d6_verboseLabel_en-US" xlink:label="lab_isba_CommonStockHeldinTrustShares" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares held in Rabbi Trust</link:label>
    <link:label id="lab_isba_CommonStockHeldinTrustShares_434f5349-f10f-48da-953f-20f4de920c6c_terseLabel_en-US" xlink:label="lab_isba_CommonStockHeldinTrustShares" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Eligible shares, shares held in Rabbi Trust</link:label>
    <link:label id="lab_isba_CommonStockHeldinTrustShares_label_en-US" xlink:label="lab_isba_CommonStockHeldinTrustShares" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock Held in Trust, Shares</link:label>
    <link:label id="lab_isba_CommonStockHeldinTrustShares_documentation_en-US" xlink:label="lab_isba_CommonStockHeldinTrustShares" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Common Stock Held in Trust, Shares</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommonStockHeldinTrustShares" xlink:href="isba-20231231.xsd#isba_CommonStockHeldinTrustShares"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommonStockHeldinTrustShares" xlink:to="lab_isba_CommonStockHeldinTrustShares" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsGross_cfe4bddb-dfc8-4da0-8fa8-b3e56ff0b064_totalLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsGross" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total deferred tax assets</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsGross_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsGross" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Gross</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsGross" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsGross"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsGross" xlink:to="lab_us-gaap_DeferredTaxAssetsGross" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_ParentCompanyMember_42d597fe-fb12-46ad-967f-a850bc8df53f_verboseLabel_en-US" xlink:label="lab_srt_ParentCompanyMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Parent Company [Member]</link:label>
    <link:label id="lab_srt_ParentCompanyMember_label_en-US" xlink:label="lab_srt_ParentCompanyMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Parent Company [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ParentCompanyMember" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ParentCompanyMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ParentCompanyMember" xlink:to="lab_srt_ParentCompanyMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DepositLiabilitiesDisclosuresTextBlock_c0129231-efbf-4f78-bd46-d6094e2a9a70_verboseLabel_en-US" xlink:label="lab_us-gaap_DepositLiabilitiesDisclosuresTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deposits</link:label>
    <link:label id="lab_us-gaap_DepositLiabilitiesDisclosuresTextBlock_label_en-US" xlink:label="lab_us-gaap_DepositLiabilitiesDisclosuresTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deposit Liabilities Disclosures [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositLiabilitiesDisclosuresTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepositLiabilitiesDisclosuresTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepositLiabilitiesDisclosuresTextBlock" xlink:to="lab_us-gaap_DepositLiabilitiesDisclosuresTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NumberOfStores_fd40f2c0-4d3c-4195-9a77-ada99c16bf58_verboseLabel_en-US" xlink:label="lab_us-gaap_NumberOfStores" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Number of location of banking operations</link:label>
    <link:label id="lab_us-gaap_NumberOfStores_label_en-US" xlink:label="lab_us-gaap_NumberOfStores" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number of Stores</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfStores" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NumberOfStores"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NumberOfStores" xlink:to="lab_us-gaap_NumberOfStores" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_d0f27573-f92c-47f0-a498-440df6796d58_totalLabel_en-US" xlink:label="lab_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net interest income after provision for loan losses</link:label>
    <link:label id="lab_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss_label_en-US" xlink:label="lab_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Income (Expense), after Provision for Loan Loss</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss" xlink:to="lab_us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval_f52496d8-b282-4088-ae2a-45f1cc4511c0_verboseLabel_en-US" xlink:label="lab_us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Amount available for dividends without regulatory approval</link:label>
    <link:label id="lab_us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval_label_en-US" xlink:label="lab_us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval" xlink:to="lab_us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonStockMember_5a81b46f-0e72-4fd0-a520-1e7c374e3d54_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common Stock</link:label>
    <link:label id="lab_us-gaap_CommonStockMember_label_en-US" xlink:label="lab_us-gaap_CommonStockMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockMember" xlink:to="lab_us-gaap_CommonStockMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestRateLockCommitmentsMember_3dc806d1-9836-44b7-91e5-a2cc018f15d3_terseLabel_en-US" xlink:label="lab_us-gaap_InterestRateLockCommitmentsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Rate Lock Commitments [Member]</link:label>
    <link:label id="lab_us-gaap_InterestRateLockCommitmentsMember_e552a729-a57f-4a32-9a5e-f396f8629e28_verboseLabel_en-US" xlink:label="lab_us-gaap_InterestRateLockCommitmentsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interest Rate Lock Commitments [Member]</link:label>
    <link:label id="lab_us-gaap_InterestRateLockCommitmentsMember_label_en-US" xlink:label="lab_us-gaap_InterestRateLockCommitmentsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Rate Lock Commitments [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateLockCommitmentsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestRateLockCommitmentsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestRateLockCommitmentsMember" xlink:to="lab_us-gaap_InterestRateLockCommitmentsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_62bb94a8-80a7-4b18-b5eb-d8b73a97d86c_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable" xlink:to="lab_us-gaap_ScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet_ed9e1e84-94f0-47c7-807a-4875b5fefbe4_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Federal Funds Purchased and Securities Sold under Agreements to Repurchase, Net</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Federal Funds Purchased and Securities Sold under Agreements to Repurchase, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet" xlink:to="lab_us-gaap_IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityAddressPostalZipCode_b0b8831a-dce4-4fc2-9ec4-d2ce84fc83a8_terseLabel_en-US" xlink:label="lab_dei_EntityAddressPostalZipCode" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Address, Postal Zip Code</link:label>
    <link:label id="lab_dei_EntityAddressPostalZipCode_label_en-US" xlink:label="lab_dei_EntityAddressPostalZipCode" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Address, Postal Zip Code</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityAddressPostalZipCode"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressPostalZipCode" xlink:to="lab_dei_EntityAddressPostalZipCode" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_GainLossOnSaleOfMortgageLoans_b21919c1-a749-4ead-a6b9-dbd91503a136_verboseLabel_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfMortgageLoans" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net gain on sale of mortgage loans</link:label>
    <link:label id="lab_us-gaap_GainLossOnSaleOfMortgageLoans_2d8a9f18-4146-4379-83b4-75e3482cff69_negatedLabel_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfMortgageLoans" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net gain on sale of mortgage loans</link:label>
    <link:label id="lab_us-gaap_GainLossOnSaleOfMortgageLoans_12b693ed-9179-4a42-9f48-064d676f3a22_terseLabel_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfMortgageLoans" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gain (Loss) on Sale of Mortgage Loans</link:label>
    <link:label id="lab_us-gaap_GainLossOnSaleOfMortgageLoans_label_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfMortgageLoans" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gain (Loss) on Sale of Mortgage Loans</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfMortgageLoans" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_GainLossOnSaleOfMortgageLoans"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnSaleOfMortgageLoans" xlink:to="lab_us-gaap_GainLossOnSaleOfMortgageLoans" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock_25e42152-7d34-4578-8981-2315bf1b8491_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Assets and liabilities measured at fair value</link:label>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock_label_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Measurements, Recurring and Nonrecurring [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock" xlink:to="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AmortizationOfMortgageServicingRightsMSRs_1aeef2cc-7ac2-4177-bd7c-a3fdc6073f89_verboseLabel_en-US" xlink:label="lab_us-gaap_AmortizationOfMortgageServicingRightsMSRs" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Amortization of OMSR</link:label>
    <link:label id="lab_us-gaap_AmortizationOfMortgageServicingRightsMSRs_0fb57d9a-1add-4074-89c9-ce89f98572d9_terseLabel_en-US" xlink:label="lab_us-gaap_AmortizationOfMortgageServicingRightsMSRs" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization of Mortgage Servicing Rights (MSRs)</link:label>
    <link:label id="lab_us-gaap_AmortizationOfMortgageServicingRightsMSRs_label_en-US" xlink:label="lab_us-gaap_AmortizationOfMortgageServicingRightsMSRs" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amortization of Mortgage Servicing Rights (MSRs)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfMortgageServicingRightsMSRs" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AmortizationOfMortgageServicingRightsMSRs"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AmortizationOfMortgageServicingRightsMSRs" xlink:to="lab_us-gaap_AmortizationOfMortgageServicingRightsMSRs" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtWeightedAverageInterestRate_05dbe997-bd20-4120-9b19-6d71986d5022_terseLabel_en-US" xlink:label="lab_us-gaap_DebtWeightedAverageInterestRate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Borrowed funds, Rate</link:label>
    <link:label id="lab_us-gaap_DebtWeightedAverageInterestRate_label_en-US" xlink:label="lab_us-gaap_DebtWeightedAverageInterestRate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt, Weighted Average Interest Rate</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtWeightedAverageInterestRate" xlink:to="lab_us-gaap_DebtWeightedAverageInterestRate" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_UnrealizedGainLossOnDerivativesAndCommodityContractsAbstract_6c12c202-32c6-4479-baa0-7b18d09af80d_terseLabel_en-US" xlink:label="lab_us-gaap_UnrealizedGainLossOnDerivativesAndCommodityContractsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unrealized Gain (Loss) on Derivatives and Commodity Contracts [Abstract]</link:label>
    <link:label id="lab_us-gaap_UnrealizedGainLossOnDerivativesAndCommodityContractsAbstract_label_en-US" xlink:label="lab_us-gaap_UnrealizedGainLossOnDerivativesAndCommodityContractsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrealized Gain (Loss) on Derivatives and Commodity Contracts [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnDerivativesAndCommodityContractsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_UnrealizedGainLossOnDerivativesAndCommodityContractsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrealizedGainLossOnDerivativesAndCommodityContractsAbstract" xlink:to="lab_us-gaap_UnrealizedGainLossOnDerivativesAndCommodityContractsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_MinimumMember_e1762dfc-6932-4fc0-90bc-fc6ca0a8a49d_verboseLabel_en-US" xlink:label="lab_srt_MinimumMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Minimum [Member]</link:label>
    <link:label id="lab_srt_MinimumMember_cd5a224b-7fa4-4488-b2f2-b162d90c4285_terseLabel_en-US" xlink:label="lab_srt_MinimumMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Minimum [Member]</link:label>
    <link:label id="lab_srt_MinimumMember_label_en-US" xlink:label="lab_srt_MinimumMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minimum [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_MinimumMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_MinimumMember" xlink:to="lab_srt_MinimumMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NoninterestIncomeOtherOperatingIncome_2b352b16-94e4-4d38-a4d8-76f24074358b_verboseLabel_en-US" xlink:label="lab_us-gaap_NoninterestIncomeOtherOperatingIncome" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_NoninterestIncomeOtherOperatingIncome_label_en-US" xlink:label="lab_us-gaap_NoninterestIncomeOtherOperatingIncome" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noninterest Income, Other Operating Income</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncomeOtherOperatingIncome" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoninterestIncomeOtherOperatingIncome"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoninterestIncomeOtherOperatingIncome" xlink:to="lab_us-gaap_NoninterestIncomeOtherOperatingIncome" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_b5a80f9f-03d3-49f2-9645-603bc3c67cb0_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Premises and equipment</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_bb0f8ea7-5705-4c00-ba57-c689018d6972_totalLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Premises and equipment, net</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_45d5fda5-b358-4acc-9b71-0dac9ab72025_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Net</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNet" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancialAssets30To89DaysPastDueMember_251170ca-b873-482c-a1e6-f3d080441a85_terseLabel_en-US" xlink:label="lab_isba_FinancialAssets30To89DaysPastDueMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Assets, 30 to 89 Days Past Due</link:label>
    <link:label id="lab_isba_FinancialAssets30To89DaysPastDueMember_label_en-US" xlink:label="lab_isba_FinancialAssets30To89DaysPastDueMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Assets, 30 to 89 Days Past Due [Member]</link:label>
    <link:label id="lab_isba_FinancialAssets30To89DaysPastDueMember_documentation_en-US" xlink:label="lab_isba_FinancialAssets30To89DaysPastDueMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financial Assets, 30 to 89 Days Past Due</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancialAssets30To89DaysPastDueMember" xlink:href="isba-20231231.xsd#isba_FinancialAssets30To89DaysPastDueMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancialAssets30To89DaysPastDueMember" xlink:to="lab_isba_FinancialAssets30To89DaysPastDueMember" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CondensedBalanceSheetStatementTable_ced63dcb-078a-48f0-aef0-3bb2f3bae1c9_terseLabel_en-US" xlink:label="lab_srt_CondensedBalanceSheetStatementTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Condensed Balance Sheet Statement [Table]</link:label>
    <link:label id="lab_srt_CondensedBalanceSheetStatementTable_label_en-US" xlink:label="lab_srt_CondensedBalanceSheetStatementTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Balance Sheet Statement [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedBalanceSheetStatementTable" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CondensedBalanceSheetStatementTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CondensedBalanceSheetStatementTable" xlink:to="lab_srt_CondensedBalanceSheetStatementTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonStockDividendsPerShareCashPaid_2308e386-33bc-4a14-8e82-f4e07194d935_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockDividendsPerShareCashPaid" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cash dividends per share (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_CommonStockDividendsPerShareCashPaid_e55cd639-efa9-4eda-a313-c247787bb1da_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockDividendsPerShareCashPaid" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash dividends per basic share (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_CommonStockDividendsPerShareCashPaid_label_en-US" xlink:label="lab_us-gaap_CommonStockDividendsPerShareCashPaid" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Dividends, Per Share, Cash Paid</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareCashPaid" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockDividendsPerShareCashPaid"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockDividendsPerShareCashPaid" xlink:to="lab_us-gaap_CommonStockDividendsPerShareCashPaid" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Cash_6c3a7c20-b04c-4e15-900e-5cfa0faa5c1b_verboseLabel_en-US" xlink:label="lab_us-gaap_Cash" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cash on deposit at subsidiary Bank</link:label>
    <link:label id="lab_us-gaap_Cash_label_en-US" xlink:label="lab_us-gaap_Cash" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Cash" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Cash"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Cash" xlink:to="lab_us-gaap_Cash" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_3375fd08-f884-4bb6-9ee3-2903baf413eb_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Unrealized gains (losses), net of tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Net of Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StatementOfCashFlowsAbstract_2b973943-f6b0-4a47-8d26-bb46bc762665_terseLabel_en-US" xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statement of Cash Flows [Abstract]</link:label>
    <link:label id="lab_us-gaap_StatementOfCashFlowsAbstract_label_en-US" xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Cash Flows [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementOfCashFlowsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract" xlink:to="lab_us-gaap_StatementOfCashFlowsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligation_52d40c31-9d20-4c01-b72e-37a90777b88b_periodStartLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Benefit obligation, January 1</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligation_36b82084-b88b-46f1-a45f-f56330c85158_periodEndLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Benefit obligation, December 31</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligation_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligation" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanBenefitObligation"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligation" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligation" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding_55c6d0df-d0cd-4504-9900-baa66b56bacd_verboseLabel_en-US" xlink:label="lab_us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Unpaid principal balance of mortgages serviced for others</link:label>
    <link:label id="lab_us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding_label_en-US" xlink:label="lab_us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Continuing Involvement with Transferred Financial Assets, Principal Amount Outstanding</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding" xlink:to="lab_us-gaap_ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AssetsAbstract_d76340c8-251a-4259-a04e-93a83e687652_verboseLabel_en-US" xlink:label="lab_us-gaap_AssetsAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">ASSETS</link:label>
    <link:label id="lab_us-gaap_AssetsAbstract_label_en-US" xlink:label="lab_us-gaap_AssetsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AssetsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsAbstract" xlink:to="lab_us-gaap_AssetsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_7a49b2ab-e58f-4ccc-adfe-6f23fdabbaa7_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year Three</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Three</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DepositsWithStatedMaturitiesFairValueDisclosure_69ede79c-12d7-4677-bb0f-593c76075a74_verboseLabel_en-US" xlink:label="lab_isba_DepositsWithStatedMaturitiesFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deposits with stated maturities</link:label>
    <link:label id="lab_isba_DepositsWithStatedMaturitiesFairValueDisclosure_label_en-US" xlink:label="lab_isba_DepositsWithStatedMaturitiesFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deposits With Stated Maturities, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_DepositsWithStatedMaturitiesFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_DepositsWithStatedMaturitiesFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deposits With Stated Maturities, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DepositsWithStatedMaturitiesFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_DepositsWithStatedMaturitiesFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DepositsWithStatedMaturitiesFairValueDisclosure" xlink:to="lab_isba_DepositsWithStatedMaturitiesFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsOther_6318f671-8f42-4520-abd4-03115a4b39f7_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsOther" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsOther_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsOther" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Other</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsOther" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsOther"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsOther" xlink:to="lab_us-gaap_DeferredTaxAssetsOther" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_USTreasurySecuritiesMember_c3b4ee04-b9fd-4cf4-90d1-cfb9ff14e725_terseLabel_en-US" xlink:label="lab_us-gaap_USTreasurySecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">US Treasury Securities</link:label>
    <link:label id="lab_us-gaap_USTreasurySecuritiesMember_label_en-US" xlink:label="lab_us-gaap_USTreasurySecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">US Treasury Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_USTreasurySecuritiesMember" xlink:to="lab_us-gaap_USTreasurySecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_cdd7faa6-ce6b-49da-92df-99d566b28696_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net cash provided by (used in) financing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RetirementPlanTypeAxis_bd97d982-fde7-4921-9c23-f6d46330dd75_terseLabel_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Retirement Plan Type [Axis]</link:label>
    <link:label id="lab_us-gaap_RetirementPlanTypeAxis_label_en-US" xlink:label="lab_us-gaap_RetirementPlanTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retirement Plan Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetirementPlanTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanTypeAxis" xlink:to="lab_us-gaap_RetirementPlanTypeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableGrossCarryingAmount_92bcd18b-2c67-4655-a334-cfe071e3c519_terseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableGrossCarryingAmount" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Gross</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableGrossCarryingAmount_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableGrossCarryingAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Gross</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableGrossCarryingAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableGrossCarryingAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableGrossCarryingAmount" xlink:to="lab_us-gaap_LoansAndLeasesReceivableGrossCarryingAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_f5425189-2d0b-4675-87ba-822acad1321b_verboseLabel_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Off-Balance-Sheet Activities</link:label>
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_35a256b6-33dd-4d8c-9b20-8da2857ec05f_terseLabel_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commitments and Other Matters</link:label>
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RetainedEarningsMember_67a45180-1930-473c-8381-286de38192f0_verboseLabel_en-US" xlink:label="lab_us-gaap_RetainedEarningsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Retained Earnings</link:label>
    <link:label id="lab_us-gaap_RetainedEarningsMember_label_en-US" xlink:label="lab_us-gaap_RetainedEarningsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retained Earnings [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetainedEarningsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetainedEarningsMember" xlink:to="lab_us-gaap_RetainedEarningsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_0f034754-e33a-46d7-8e46-0347b5b1cdb4_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EarningsPerShareBasic_5881cc2d-db85-4878-be2d-a3852ef27315_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Basic (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareBasic_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Basic</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasic" xlink:to="lab_us-gaap_EarningsPerShareBasic" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CertificatesOfDepositUnderOtherSavings_449495b2-27d9-4737-887e-43a81f100a96_verboseLabel_en-US" xlink:label="lab_isba_CertificatesOfDepositUnderOtherSavings" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Certificates of deposit under $100 and other savings</link:label>
    <link:label id="lab_isba_CertificatesOfDepositUnderOtherSavings_label_en-US" xlink:label="lab_isba_CertificatesOfDepositUnderOtherSavings" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Certificates of Deposit under Other Savings</link:label>
    <link:label id="lab_isba_CertificatesOfDepositUnderOtherSavings_documentation_en-US" xlink:label="lab_isba_CertificatesOfDepositUnderOtherSavings" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Certificates of deposit under $100 and other savings.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CertificatesOfDepositUnderOtherSavings" xlink:href="isba-20231231.xsd#isba_CertificatesOfDepositUnderOtherSavings"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CertificatesOfDepositUnderOtherSavings" xlink:to="lab_isba_CertificatesOfDepositUnderOtherSavings" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_SelfFundedMedicalPlanExpensesDuringPeriod_732a59cc-2293-4d89-9515-3c2382efae2c_verboseLabel_en-US" xlink:label="lab_isba_SelfFundedMedicalPlanExpensesDuringPeriod" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Medical expenses</link:label>
    <link:label id="lab_isba_SelfFundedMedicalPlanExpensesDuringPeriod_label_en-US" xlink:label="lab_isba_SelfFundedMedicalPlanExpensesDuringPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Self Funded Medical Plan Expenses During Period</link:label>
    <link:label id="lab_isba_SelfFundedMedicalPlanExpensesDuringPeriod_documentation_en-US" xlink:label="lab_isba_SelfFundedMedicalPlanExpensesDuringPeriod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Self funded medical plan expenses during period.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_SelfFundedMedicalPlanExpensesDuringPeriod" xlink:href="isba-20231231.xsd#isba_SelfFundedMedicalPlanExpensesDuringPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_SelfFundedMedicalPlanExpensesDuringPeriod" xlink:to="lab_isba_SelfFundedMedicalPlanExpensesDuringPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccountingPoliciesAbstract_9e7ac180-bec9-4cad-ba24-d8a36ece8a9a_terseLabel_en-US" xlink:label="lab_us-gaap_AccountingPoliciesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounting Policies [Abstract]</link:label>
    <link:label id="lab_us-gaap_AccountingPoliciesAbstract_label_en-US" xlink:label="lab_us-gaap_AccountingPoliciesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Policies [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountingPoliciesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccountingPoliciesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingPoliciesAbstract" xlink:to="lab_us-gaap_AccountingPoliciesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks_ba33a384-9381-4f9f-9884-3170dc1f61f1_terseLabel_en-US" xlink:label="lab_isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash reserve balance, correspondent banks</link:label>
    <link:label id="lab_isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks_label_en-US" xlink:label="lab_isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash Reserve Deposit Required And Made By Correspondent Banks</link:label>
    <link:label id="lab_isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks_documentation_en-US" xlink:label="lab_isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Cash Reserve Deposit Required And Made By Correspondent Banks</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks" xlink:href="isba-20231231.xsd#isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks" xlink:to="lab_isba_CashReserveDepositRequiredAndMadeByCorrespondentBanks" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_a896e7b6-b423-4bc6-b206-b211bdeaeeb0_totalLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net deferred tax assets (liabilities)</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsLiabilitiesNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsLiabilitiesNet" xlink:to="lab_us-gaap_DeferredTaxAssetsLiabilitiesNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_8f0e9d49-90f5-4bcb-ba87-15ec51d7291f_periodStartLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Fair value of plan assets, January 1</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_b9ea073e-f7d8-447a-932f-bfd55fdcba63_periodEndLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Fair value of plan assets, December 31</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_185ab3ed-e361-4ae0-9f0d-9d5ff0b6b410_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Fair values of the Corporation's pension plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanFairValueOfPlanAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:to="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProvisionForLoanLeaseAndOtherLosses_54348aa2-20e1-4f5d-871f-95ecf712a312_terseLabel_en-US" xlink:label="lab_us-gaap_ProvisionForLoanLeaseAndOtherLosses" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Provision for loan losses</link:label>
    <link:label id="lab_us-gaap_ProvisionForLoanLeaseAndOtherLosses_label_en-US" xlink:label="lab_us-gaap_ProvisionForLoanLeaseAndOtherLosses" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Provision for Loan, Lease, and Other Losses</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForLoanLeaseAndOtherLosses" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProvisionForLoanLeaseAndOtherLosses"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProvisionForLoanLeaseAndOtherLosses" xlink:to="lab_us-gaap_ProvisionForLoanLeaseAndOtherLosses" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock_303127ac-7c9f-48aa-b1c9-1a5d62e16f5c_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Unrealized Loss Position, Fair Value</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionFairValueTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CapitalToRiskWeightedAssets_c83d0275-be05-4397-9bf6-9690b2d0ffe9_verboseLabel_en-US" xlink:label="lab_us-gaap_CapitalToRiskWeightedAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Actual Ratio</link:label>
    <link:label id="lab_us-gaap_CapitalToRiskWeightedAssets_label_en-US" xlink:label="lab_us-gaap_CapitalToRiskWeightedAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Total Risk-Based Capital Ratio, Actual</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalToRiskWeightedAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CapitalToRiskWeightedAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalToRiskWeightedAssets" xlink:to="lab_us-gaap_CapitalToRiskWeightedAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_c18e4a3a-625a-4010-9ad5-a993cd96f885_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Benefits Paid</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Benefits Paid</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialAdvancestoMortgageBrokersSegmentMember_5c50cde2-2042-4e32-883a-7ccdabd40502_terseLabel_en-US" xlink:label="lab_isba_CommercialAdvancestoMortgageBrokersSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial Advances to Mortgage Brokers Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialAdvancestoMortgageBrokersSegmentMember_label_en-US" xlink:label="lab_isba_CommercialAdvancestoMortgageBrokersSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Advances to Mortgage Brokers Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialAdvancestoMortgageBrokersSegmentMember_documentation_en-US" xlink:label="lab_isba_CommercialAdvancestoMortgageBrokersSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial Advances to Mortgage Brokers Segment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialAdvancestoMortgageBrokersSegmentMember" xlink:href="isba-20231231.xsd#isba_CommercialAdvancestoMortgageBrokersSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialAdvancestoMortgageBrokersSegmentMember" xlink:to="lab_isba_CommercialAdvancestoMortgageBrokersSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonStockHeldInTrust_552880c9-87dd-4437-aa44-21a571cb953d_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockHeldInTrust" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Market value, shares held in Rabbi Trust</link:label>
    <link:label id="lab_us-gaap_CommonStockHeldInTrust_label_en-US" xlink:label="lab_us-gaap_CommonStockHeldInTrust" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock Held in Trust</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockHeldInTrust" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockHeldInTrust"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockHeldInTrust" xlink:to="lab_us-gaap_CommonStockHeldInTrust" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeTaxesPaid_d771dabd-9f42-4427-a575-c38c791dbfba_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxesPaid" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Federal income taxes paid</link:label>
    <link:label id="lab_us-gaap_IncomeTaxesPaid_label_en-US" xlink:label="lab_us-gaap_IncomeTaxesPaid" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Taxes Paid</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxesPaid" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxesPaid"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxesPaid" xlink:to="lab_us-gaap_IncomeTaxesPaid" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ConsolidationPolicyTextBlock_fbdb1ef8-9c55-40d0-b1b7-87f1a93b7981_terseLabel_en-US" xlink:label="lab_us-gaap_ConsolidationPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consolidation</link:label>
    <link:label id="lab_us-gaap_ConsolidationPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_ConsolidationPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consolidation, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsolidationPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConsolidationPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConsolidationPolicyTextBlock" xlink:to="lab_us-gaap_ConsolidationPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized_015c0703-020a-4f65-b25b-4601fb2d5497_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount</link:label>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized_label_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Risk-Based Capital, Well Capitalized, Minimum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized" xlink:to="lab_us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableModifiedPastDueTableTextBlock_b5ae9e4d-19ad-4454-8bde-95d30bc27e35_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableModifiedPastDueTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Modified, Past Due</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableModifiedPastDueTableTextBlock_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableModifiedPastDueTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Modified, Past Due [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModifiedPastDueTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableModifiedPastDueTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableModifiedPastDueTableTextBlock" xlink:to="lab_us-gaap_FinancingReceivableModifiedPastDueTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock_ce0e05f2-68ab-4a57-9a0b-b872770b5760_verboseLabel_en-US" xlink:label="lab_us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">OFF BALANCE SHEET CREDIT RELATED FINANCIAL INSTRUMENTS</link:label>
    <link:label id="lab_us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Off-Balance-Sheet Credit Exposure, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock" xlink:to="lab_us-gaap_OffBalanceSheetCreditExposurePolicyPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentTransitionReport_aa747561-359e-414b-91e3-f0339400c41f_terseLabel_en-US" xlink:label="lab_dei_DocumentTransitionReport" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Transition Report</link:label>
    <link:label id="lab_dei_DocumentTransitionReport_label_en-US" xlink:label="lab_dei_DocumentTransitionReport" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Transition Report</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentTransitionReport" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentTransitionReport"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentTransitionReport" xlink:to="lab_dei_DocumentTransitionReport" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityPublicFloat_b97fb664-f935-405b-a485-cbcf41f79acf_terseLabel_en-US" xlink:label="lab_dei_EntityPublicFloat" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Public Float</link:label>
    <link:label id="lab_dei_EntityPublicFloat_label_en-US" xlink:label="lab_dei_EntityPublicFloat" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Public Float</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityPublicFloat" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityPublicFloat"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityPublicFloat" xlink:to="lab_dei_EntityPublicFloat" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_74e6ea93-550b-495d-8be9-51069a2a45b1_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_label_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfSubordinatedLongTermDebt_522befb8-c8dc-49f1-9275-c27a23da4925_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfSubordinatedLongTermDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from Issuance of Subordinated Long-term Debt</link:label>
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfSubordinatedLongTermDebt_label_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfSubordinatedLongTermDebt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Issuance of Subordinated Long-Term Debt</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfSubordinatedLongTermDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromIssuanceOfSubordinatedLongTermDebt"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfSubordinatedLongTermDebt" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfSubordinatedLongTermDebt" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ResidentialMortgageMember_e6c36c27-148e-4acb-8473-79906d9f45e9_terseLabel_en-US" xlink:label="lab_us-gaap_ResidentialMortgageMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Residential Mortgage</link:label>
    <link:label id="lab_us-gaap_ResidentialMortgageMember_label_en-US" xlink:label="lab_us-gaap_ResidentialMortgageMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Residential Mortgage [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ResidentialMortgageMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ResidentialMortgageMember" xlink:to="lab_us-gaap_ResidentialMortgageMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentAbstract_89be46dd-c16f-431b-b861-7c42993deb9d_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Abstract]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentAbstract_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DerivativeInstrumentRiskAxis_5d2f0a73-69d6-43a3-910b-92f39a096b9c_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeInstrumentRiskAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative Instrument [Axis]</link:label>
    <link:label id="lab_us-gaap_DerivativeInstrumentRiskAxis_label_en-US" xlink:label="lab_us-gaap_DerivativeInstrumentRiskAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Instrument [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis" xlink:to="lab_us-gaap_DerivativeInstrumentRiskAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PreAdoptionAllowanceMember_af7aaf64-9721-4e6c-83b7-99bd010a3cd2_terseLabel_en-US" xlink:label="lab_isba_PreAdoptionAllowanceMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pre Adoption Allowance</link:label>
    <link:label id="lab_isba_PreAdoptionAllowanceMember_label_en-US" xlink:label="lab_isba_PreAdoptionAllowanceMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pre Adoption Allowance [Member]</link:label>
    <link:label id="lab_isba_PreAdoptionAllowanceMember_documentation_en-US" xlink:label="lab_isba_PreAdoptionAllowanceMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pre Adoption Allowance</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PreAdoptionAllowanceMember" xlink:href="isba-20231231.xsd#isba_PreAdoptionAllowanceMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PreAdoptionAllowanceMember" xlink:to="lab_isba_PreAdoptionAllowanceMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubstandardMember_9dc18c1b-308f-4cb6-b0ac-2d549d14e1ea_terseLabel_en-US" xlink:label="lab_us-gaap_SubstandardMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Substandard [Member]</link:label>
    <link:label id="lab_us-gaap_SubstandardMember_label_en-US" xlink:label="lab_us-gaap_SubstandardMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Substandard [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubstandardMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubstandardMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubstandardMember" xlink:to="lab_us-gaap_SubstandardMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock_5ac1575f-2c37-4e89-830f-29642e5ad6c2_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Notional amount of financial instrument</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Fair Value, off-Balance-Sheet Risks [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock" xlink:to="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableAllowanceForLoanLossesPolicy_3430632e-6269-4ca6-9b53-7bb9f79fd4bf_terseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableAllowanceForLoanLossesPolicy" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Allowance for Credit Losses - Loans</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableAllowanceForLoanLossesPolicy_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableAllowanceForLoanLossesPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Allowance for Loan Losses Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableAllowanceForLoanLossesPolicy" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableAllowanceForLoanLossesPolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableAllowanceForLoanLossesPolicy" xlink:to="lab_us-gaap_LoansAndLeasesReceivableAllowanceForLoanLossesPolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_e474444f-b021-44e4-a34c-97ed0b43500d_terseLabel_en-US" xlink:label="lab_isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets</link:label>
    <link:label id="lab_isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_label_en-US" xlink:label="lab_isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_documentation_en-US" xlink:label="lab_isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:href="isba-20231231.xsd#isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:to="lab_isba_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RelatedPartyDepositLiabilities_011731d7-89ed-40ed-9128-df8fd31fd3ad_verboseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyDepositLiabilities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total deposits</link:label>
    <link:label id="lab_us-gaap_RelatedPartyDepositLiabilities_label_en-US" xlink:label="lab_us-gaap_RelatedPartyDepositLiabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Deposit Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDepositLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyDepositLiabilities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyDepositLiabilities" xlink:to="lab_us-gaap_RelatedPartyDepositLiabilities" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_627e58fd-a3e3-4f0a-a7b3-aa681c3ae185_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred income tax expense (benefit)</link:label>
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_4957ba89-b3a1-4e82-9203-7d1260e419ca_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred Income Tax Expense (Benefit)</link:label>
    <link:label id="lab_us-gaap_DeferredIncomeTaxExpenseBenefit_label_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:to="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_f47c493b-490d-4d1f-91b4-6613f1d997c9_terseLabel_en-US" xlink:label="lab_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statement of Comprehensive Income [Abstract]</link:label>
    <link:label id="lab_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract_label_en-US" xlink:label="lab_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Comprehensive Income [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="lab_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LoansReceivableCollateralizedByEquipmentMember_840a416f-33cb-4a55-beef-f4f85f8a4bf8_verboseLabel_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByEquipmentMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Equipment [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByEquipmentMember_label_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByEquipmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Equipment [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByEquipmentMember_documentation_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByEquipmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Equipment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LoansReceivableCollateralizedByEquipmentMember" xlink:href="isba-20231231.xsd#isba_LoansReceivableCollateralizedByEquipmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LoansReceivableCollateralizedByEquipmentMember" xlink:to="lab_isba_LoansReceivableCollateralizedByEquipmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentFinStmtErrorCorrectionFlag_4c7c14d6-276a-40f0-b219-13824c9fd681_terseLabel_en-US" xlink:label="lab_dei_DocumentFinStmtErrorCorrectionFlag" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Annual Report</link:label>
    <link:label id="lab_dei_DocumentFinStmtErrorCorrectionFlag_label_en-US" xlink:label="lab_dei_DocumentFinStmtErrorCorrectionFlag" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Financial Statement Error Correction [Flag]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFinStmtErrorCorrectionFlag" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentFinStmtErrorCorrectionFlag"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentFinStmtErrorCorrectionFlag" xlink:to="lab_dei_DocumentFinStmtErrorCorrectionFlag" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_11d3df24-bbfe-4f46-905a-2cf0765ef8e8_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Forfeited (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DepositsAbstract_697dc84c-30f2-4350-8e14-99f007f75a13_verboseLabel_en-US" xlink:label="lab_us-gaap_DepositsAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deposits</link:label>
    <link:label id="lab_us-gaap_DepositsAbstract_d0fb1c57-a5cb-406f-8110-382020ec9491_terseLabel_en-US" xlink:label="lab_us-gaap_DepositsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deposits [Abstract]</link:label>
    <link:label id="lab_us-gaap_DepositsAbstract_label_en-US" xlink:label="lab_us-gaap_DepositsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deposits [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepositsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepositsAbstract" xlink:to="lab_us-gaap_DepositsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ConsumerSecuredDirectPortfolioSegmentMember_ec42f074-d4ea-48c0-b50d-611f5be5619f_terseLabel_en-US" xlink:label="lab_isba_ConsumerSecuredDirectPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consumer, Secured, Direct, Portfolio Segment</link:label>
    <link:label id="lab_isba_ConsumerSecuredDirectPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_ConsumerSecuredDirectPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consumer, Secured, Direct, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_ConsumerSecuredDirectPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_ConsumerSecuredDirectPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Consumer, Secured, Direct, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ConsumerSecuredDirectPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_ConsumerSecuredDirectPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ConsumerSecuredDirectPortfolioSegmentMember" xlink:to="lab_isba_ConsumerSecuredDirectPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_3a131887-f277-4905-bf66-e854d23b560a_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Employee contribution, percent</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:to="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation_6cc1609a-911f-42fe-b940-aef66f980533_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Accumulated Benefit Obligation</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Accumulated Benefit Obligation</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xlink:to="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherAssets_bbf6bf46-6d23-473a-9162-e660b7ad175a_terseLabel_en-US" xlink:label="lab_us-gaap_OtherAssets" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other assets</link:label>
    <link:label id="lab_us-gaap_OtherAssets_label_en-US" xlink:label="lab_us-gaap_OtherAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAssets" xlink:to="lab_us-gaap_OtherAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_AuctionRateMoneyMarketPreferredStocksMember_0fe68ec6-2a36-4065-a769-6b5cb3835969_terseLabel_en-US" xlink:label="lab_isba_AuctionRateMoneyMarketPreferredStocksMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Auction Rate Money Market Preferred and Preferred Stocks [Member]</link:label>
    <link:label id="lab_isba_AuctionRateMoneyMarketPreferredStocksMember_label_en-US" xlink:label="lab_isba_AuctionRateMoneyMarketPreferredStocksMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Auction Rate Money Market Preferred Stocks [Member]</link:label>
    <link:label id="lab_isba_AuctionRateMoneyMarketPreferredStocksMember_documentation_en-US" xlink:label="lab_isba_AuctionRateMoneyMarketPreferredStocksMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Auction Rate Money Market Preferred Stocks [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_AuctionRateMoneyMarketPreferredStocksMember" xlink:href="isba-20231231.xsd#isba_AuctionRateMoneyMarketPreferredStocksMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_AuctionRateMoneyMarketPreferredStocksMember" xlink:to="lab_isba_AuctionRateMoneyMarketPreferredStocksMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_0a30ad67-da9c-4adf-94d1-dd7b3785e2a4_verboseLabel_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Average potential effect of common shares in the Directors Plan</link:label>
    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_d415bb17-9d19-415a-988f-39bbb43ab1c1_terseLabel_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements</link:label>
    <link:label id="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_label_en-US" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:to="lab_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CondensedCashFlowStatementsCaptionsLineItems_37225a56-2298-49c9-b103-90d4f3594302_terseLabel_en-US" xlink:label="lab_srt_CondensedCashFlowStatementsCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Condensed Cash Flow Statements, Captions [Line Items]</link:label>
    <link:label id="lab_srt_CondensedCashFlowStatementsCaptionsLineItems_label_en-US" xlink:label="lab_srt_CondensedCashFlowStatementsCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Cash Flow Statements, Captions [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedCashFlowStatementsCaptionsLineItems" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CondensedCashFlowStatementsCaptionsLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems" xlink:to="lab_srt_CondensedCashFlowStatementsCaptionsLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentPeriodEndDate_0f51a4eb-87bf-4c13-ab5e-3d734f2f7280_terseLabel_en-US" xlink:label="lab_dei_DocumentPeriodEndDate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Period End Date</link:label>
    <link:label id="lab_dei_DocumentPeriodEndDate_label_en-US" xlink:label="lab_dei_DocumentPeriodEndDate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Period End Date</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentPeriodEndDate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentPeriodEndDate" xlink:to="lab_dei_DocumentPeriodEndDate" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock_eab61ac0-8436-4b8d-b811-076f8fd3b06e_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Nonaccrual Loans with No ACL</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Nonaccrual [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfFinancingReceivablesNonAccrualStatusTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DepositsWithoutStatedMaturitiesFairValueDisclosure_07da1f16-d2f6-41d5-a498-884fc0f3e3c4_verboseLabel_en-US" xlink:label="lab_isba_DepositsWithoutStatedMaturitiesFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deposits without stated maturities</link:label>
    <link:label id="lab_isba_DepositsWithoutStatedMaturitiesFairValueDisclosure_label_en-US" xlink:label="lab_isba_DepositsWithoutStatedMaturitiesFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deposits Without Stated Maturities, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_DepositsWithoutStatedMaturitiesFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_DepositsWithoutStatedMaturitiesFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deposits Without Stated Maturities, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DepositsWithoutStatedMaturitiesFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_DepositsWithoutStatedMaturitiesFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DepositsWithoutStatedMaturitiesFairValueDisclosure" xlink:to="lab_isba_DepositsWithoutStatedMaturitiesFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_f1512eea-b6cc-4f61-a8f3-58ec812a7b51_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Member]</link:label>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember_label_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" xlink:to="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions_bc3cbad2-644a-4654-85d0-72f913868188_verboseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">New loans</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Related Parties, Additions</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions" xlink:to="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsToAcquireLifeInsurancePolicies_bec25d18-4a96-4a76-9e8a-55f6595cf138_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireLifeInsurancePolicies" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Payment to Acquire Life Insurance Policy, Investing Activities</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquireLifeInsurancePolicies_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireLifeInsurancePolicies" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payment to Acquire Life Insurance Policy, Investing Activities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireLifeInsurancePolicies" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsToAcquireLifeInsurancePolicies"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireLifeInsurancePolicies" xlink:to="lab_us-gaap_PaymentsToAcquireLifeInsurancePolicies" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_f3fe0a70-6daf-4718-89db-d4d6444c61d9_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Federal income tax expense</link:label>
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_f41d92c5-bc4a-4202-bdc1-432330a4738d_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Federal income tax benefit</link:label>
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_label_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit" xlink:to="lab_us-gaap_IncomeTaxExpenseBenefit" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PerformanceBonusExpenseExecutivePlan_245b29d9-96e2-4d19-933b-1bcc4ab6662a_terseLabel_en-US" xlink:label="lab_isba_PerformanceBonusExpenseExecutivePlan" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Performance Bonus Expense - Executive Plan</link:label>
    <link:label id="lab_isba_PerformanceBonusExpenseExecutivePlan_label_en-US" xlink:label="lab_isba_PerformanceBonusExpenseExecutivePlan" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Performance Bonus Expense - Executive Plan</link:label>
    <link:label id="lab_isba_PerformanceBonusExpenseExecutivePlan_documentation_en-US" xlink:label="lab_isba_PerformanceBonusExpenseExecutivePlan" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Performance Bonus Expense - Executive Plan</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PerformanceBonusExpenseExecutivePlan" xlink:href="isba-20231231.xsd#isba_PerformanceBonusExpenseExecutivePlan"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PerformanceBonusExpenseExecutivePlan" xlink:to="lab_isba_PerformanceBonusExpenseExecutivePlan" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate_be74b85b-f1c9-4cb9-85d3-860afe22cdec_terseLabel_en-US" xlink:label="lab_isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pledged Financial Instruments, Available for Sale Securities, without Single Maturity Date</link:label>
    <link:label id="lab_isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate_label_en-US" xlink:label="lab_isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pledged Financial Instruments, Available for Sale Securities, without Single Maturity Date</link:label>
    <link:label id="lab_isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate_documentation_en-US" xlink:label="lab_isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pledged Financial Instruments, Available for Sale Securities, without Single Maturity Date</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate" xlink:href="isba-20231231.xsd#isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate" xlink:to="lab_isba_PledgedFinancialInstrumentsAvailableforSaleSecuritieswithoutSingleMaturityDate" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ValuationTechniqueDomain_9256f42c-9130-4db2-a573-8d67c2bb1a58_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationTechniqueDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Valuation Approach and Technique [Domain]</link:label>
    <link:label id="lab_us-gaap_ValuationTechniqueDomain_label_en-US" xlink:label="lab_us-gaap_ValuationTechniqueDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Valuation Approach and Technique [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ValuationTechniqueDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationTechniqueDomain" xlink:to="lab_us-gaap_ValuationTechniqueDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs_58178a1a-71eb-41b4-8411-7281745ab82a_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Losses, Write-downs</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs_58c67df9-9753-4c7d-897a-60563c4fa4f7_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Loss, Writeoff</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Loss, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs" xlink:to="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueDisclosuresTextBlock_5d3a79f8-822a-45ef-881e-780d6b8544dc_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueDisclosuresTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Fair Value</link:label>
    <link:label id="lab_us-gaap_FairValueDisclosuresTextBlock_label_en-US" xlink:label="lab_us-gaap_FairValueDisclosuresTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Disclosures [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosuresTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueDisclosuresTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosuresTextBlock" xlink:to="lab_us-gaap_FairValueDisclosuresTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProvisionForLoanLossesExpensed_0757f494-5a70-4344-b1fa-10f25428a10a_terseLabel_en-US" xlink:label="lab_us-gaap_ProvisionForLoanLossesExpensed" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Credit Loss, Expense (Reversal)</link:label>
    <link:label id="lab_us-gaap_ProvisionForLoanLossesExpensed_label_en-US" xlink:label="lab_us-gaap_ProvisionForLoanLossesExpensed" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Credit Loss, Expense (Reversal)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForLoanLossesExpensed" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProvisionForLoanLossesExpensed"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProvisionForLoanLossesExpensed" xlink:to="lab_us-gaap_ProvisionForLoanLossesExpensed" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_9763c5b5-9388-4c00-a3ae-f737c149d44d_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EquityAbstract_d279406b-2478-448f-b2a6-6e7bbe828000_terseLabel_en-US" xlink:label="lab_us-gaap_EquityAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity [Abstract]</link:label>
    <link:label id="lab_us-gaap_EquityAbstract_label_en-US" xlink:label="lab_us-gaap_EquityAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityAbstract" xlink:to="lab_us-gaap_EquityAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_0fd7c6e9-8dee-4ccc-98e3-8d136e5335e7_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale [Line Items]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:to="lab_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiduciaryAndTrustMember_4944c420-db03-48c0-be8d-360e2ad12c0c_terseLabel_en-US" xlink:label="lab_us-gaap_FiduciaryAndTrustMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fiduciary and Trust [Member]</link:label>
    <link:label id="lab_us-gaap_FiduciaryAndTrustMember_label_en-US" xlink:label="lab_us-gaap_FiduciaryAndTrustMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fiduciary and Trust [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiduciaryAndTrustMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiduciaryAndTrustMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiduciaryAndTrustMember" xlink:to="lab_us-gaap_FiduciaryAndTrustMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome_ed45ffd6-4ff6-426b-999f-a0a0ead79db9_terseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Net of Deferred Income</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Net of Deferred Income</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome" xlink:to="lab_us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivables60To89DaysPastDueMember_10ebbaa6-2b62-465f-8f97-8b3614e70276_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivables60To89DaysPastDueMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Assets, 60 to 89 Days Past Due [Member]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivables60To89DaysPastDueMember_label_en-US" xlink:label="lab_us-gaap_FinancingReceivables60To89DaysPastDueMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Asset, 60 to 89 Days Past Due [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivables60To89DaysPastDueMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember" xlink:to="lab_us-gaap_FinancingReceivables60To89DaysPastDueMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_InterestPayableAndOtherLiabilities_5a359412-9994-4d75-9b92-8d66b79ab183_verboseLabel_en-US" xlink:label="lab_isba_InterestPayableAndOtherLiabilities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accrued interest payable and other liabilities</link:label>
    <link:label id="lab_isba_InterestPayableAndOtherLiabilities_label_en-US" xlink:label="lab_isba_InterestPayableAndOtherLiabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Payable And Other Liabilities</link:label>
    <link:label id="lab_isba_InterestPayableAndOtherLiabilities_documentation_en-US" xlink:label="lab_isba_InterestPayableAndOtherLiabilities" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Interest Payable And Other Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_InterestPayableAndOtherLiabilities" xlink:href="isba-20231231.xsd#isba_InterestPayableAndOtherLiabilities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_InterestPayableAndOtherLiabilities" xlink:to="lab_isba_InterestPayableAndOtherLiabilities" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember_bca1245e-cbaa-47ff-acf6-3328f143b7c4_terseLabel_en-US" xlink:label="lab_isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial and Industrial, Unsecured, Portfolio Segment</link:label>
    <link:label id="lab_isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial and Industrial, Unsecured, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial and Industrial, Unsecured, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember" xlink:to="lab_isba_CommercialAndIndustrialUnsecuredPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestExpenseDeposits_13bd08a7-3a02-4a33-8655-b0f62b12b99f_verboseLabel_en-US" xlink:label="lab_us-gaap_InterestExpenseDeposits" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deposits</link:label>
    <link:label id="lab_us-gaap_InterestExpenseDeposits_label_en-US" xlink:label="lab_us-gaap_InterestExpenseDeposits" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense, Deposits</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDeposits" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestExpenseDeposits"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpenseDeposits" xlink:to="lab_us-gaap_InterestExpenseDeposits" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_1aca34b5-bd23-45da-8509-b1e0827cd43b_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Amortization of unrecognized actuarial net loss</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Amortization of Gain (Loss)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:to="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancialInstrumentPerformanceStatusAxis_0b707bcb-0023-4e07-af11-61be3497d8de_terseLabel_en-US" xlink:label="lab_us-gaap_FinancialInstrumentPerformanceStatusAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Instrument Performance Status [Axis]</link:label>
    <link:label id="lab_us-gaap_FinancialInstrumentPerformanceStatusAxis_label_en-US" xlink:label="lab_us-gaap_FinancialInstrumentPerformanceStatusAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instrument Performance Status [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancialInstrumentPerformanceStatusAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusAxis" xlink:to="lab_us-gaap_FinancialInstrumentPerformanceStatusAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_f524896d-1d6b-4436-ba3d-afb41d9accbf_verboseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Gross Unrealized Losses, Less Than Twelve Months</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_6cf205a0-9189-429f-a3fc-612160d56055_totalLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total cash and cash equivalents</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, at Carrying Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:to="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_06d132ba-01da-40a1-a96b-c2458693901c_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Credit Quality Indicator [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Credit Quality Indicator [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable" xlink:to="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PastDueFinancingReceivablesTableTextBlock_92839a64-815f-44dd-b881-52bca1f1898f_verboseLabel_en-US" xlink:label="lab_us-gaap_PastDueFinancingReceivablesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of past due loans</link:label>
    <link:label id="lab_us-gaap_PastDueFinancingReceivablesTableTextBlock_label_en-US" xlink:label="lab_us-gaap_PastDueFinancingReceivablesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Past Due [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PastDueFinancingReceivablesTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PastDueFinancingReceivablesTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PastDueFinancingReceivablesTableTextBlock" xlink:to="lab_us-gaap_PastDueFinancingReceivablesTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_33531c14-57d9-42fd-b853-302590fc2201_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Expected long-term return on plan assets</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod_37eabef2-3bf5-4390-9f90-bdfb3eccc81c_negatedTerseLabel_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Forfeited</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod_label_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Forfeited in Period</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod_documentation_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Forfeited in Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod" xlink:href="isba-20231231.xsd#isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod" xlink:to="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueForfeitedInPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CreditFacilityDomain_3b66240a-d2c8-4b29-8777-160d5fc0b8b4_terseLabel_en-US" xlink:label="lab_us-gaap_CreditFacilityDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit Facility [Domain]</link:label>
    <link:label id="lab_us-gaap_CreditFacilityDomain_label_en-US" xlink:label="lab_us-gaap_CreditFacilityDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Facility [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CreditFacilityDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CreditFacilityDomain" xlink:to="lab_us-gaap_CreditFacilityDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_3cfa0af0-f09f-4ed0-bacd-5da76999be1f_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Useful lives of the related assets</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Useful Life</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent_04cd7213-bf54-469b-acf3-0e02eff22d33_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Tax effect</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax, Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent" xlink:to="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansTaxPortionAttributableToParent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate_e7ece5cc-9faa-4cd0-9003-c9939b675275_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialRealEstateNonOwnerOccupiedMember_634c1820-1497-4c38-98b3-76ceaafd05e8_terseLabel_en-US" xlink:label="lab_isba_CommercialRealEstateNonOwnerOccupiedMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, Non-owner Occupied</link:label>
    <link:label id="lab_isba_CommercialRealEstateNonOwnerOccupiedMember_label_en-US" xlink:label="lab_isba_CommercialRealEstateNonOwnerOccupiedMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, Non-owner Occupied [Member]</link:label>
    <link:label id="lab_isba_CommercialRealEstateNonOwnerOccupiedMember_documentation_en-US" xlink:label="lab_isba_CommercialRealEstateNonOwnerOccupiedMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, Non-owner Occupied</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialRealEstateNonOwnerOccupiedMember" xlink:href="isba-20231231.xsd#isba_CommercialRealEstateNonOwnerOccupiedMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialRealEstateNonOwnerOccupiedMember" xlink:to="lab_isba_CommercialRealEstateNonOwnerOccupiedMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestAndDividendIncomeOperating_47e232c2-7439-4240-b0ef-d4ffbbd66e1f_totalLabel_en-US" xlink:label="lab_us-gaap_InterestAndDividendIncomeOperating" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total interest income</link:label>
    <link:label id="lab_us-gaap_InterestAndDividendIncomeOperating_label_en-US" xlink:label="lab_us-gaap_InterestAndDividendIncomeOperating" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest and Dividend Income, Operating</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeOperating" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestAndDividendIncomeOperating"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestAndDividendIncomeOperating" xlink:to="lab_us-gaap_InterestAndDividendIncomeOperating" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2_95c734bf-945b-4dbd-a793-69bf930ffc4e_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Pre-Modification Recorded Investment</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Troubled Debt Restructuring, Premodification</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2" xlink:to="lab_us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableModificationPaymentDelay_416570d4-82b1-4cfa-b02f-c60163eaac2b_terseLabel_en-US" xlink:label="lab_isba_FinancingReceivableModificationPaymentDelay" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable Modification Payment Delay</link:label>
    <link:label id="lab_isba_FinancingReceivableModificationPaymentDelay_label_en-US" xlink:label="lab_isba_FinancingReceivableModificationPaymentDelay" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable Modification Payment Delay</link:label>
    <link:label id="lab_isba_FinancingReceivableModificationPaymentDelay_documentation_en-US" xlink:label="lab_isba_FinancingReceivableModificationPaymentDelay" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable Modification Payment Delay</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableModificationPaymentDelay" xlink:href="isba-20231231.xsd#isba_FinancingReceivableModificationPaymentDelay"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableModificationPaymentDelay" xlink:to="lab_isba_FinancingReceivableModificationPaymentDelay" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod_18115df4-5a26-4d8b-b6fe-8d94d7576440_verboseLabel_en-US" xlink:label="lab_isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Number of days past due (or more), accrual of interest discontinued</link:label>
    <link:label id="lab_isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod_label_en-US" xlink:label="lab_isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Nonperforming, Nonaccrual Of Interest, Threshold Period</link:label>
    <link:label id="lab_isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod_documentation_en-US" xlink:label="lab_isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable, Nonperforming, Nonaccrual Of Interest, Threshold Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod" xlink:href="isba-20231231.xsd#isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod" xlink:to="lab_isba_FinancingReceivableNonperformingNonaccrualOfInterestThresholdPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_AgriculturalPortfolioSegmentMember_218cf6f8-8e60-4f62-8dda-1db6b75af324_terseLabel_en-US" xlink:label="lab_isba_AgriculturalPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Agricultural [Member]</link:label>
    <link:label id="lab_isba_AgriculturalPortfolioSegmentMember_bced1dfe-a5de-4834-8254-477fe5ee4ea9_verboseLabel_en-US" xlink:label="lab_isba_AgriculturalPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total agricultural [Member]</link:label>
    <link:label id="lab_isba_AgriculturalPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_AgriculturalPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Agricultural Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_AgriculturalPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_AgriculturalPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Agricultural portfolio segment.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_AgriculturalPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_AgriculturalPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_AgriculturalPortfolioSegmentMember" xlink:to="lab_isba_AgriculturalPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_676d87ff-dc99-484a-95e3-bcbd66e7119a_terseLabel_en-US" xlink:label="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_label_en-US" xlink:label="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_documentation_en-US" xlink:label="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:href="isba-20231231.xsd#isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:to="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerTextBlock_978dd88e-4d80-49fb-a909-fa0c5e09e3fb_terseLabel_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer [Text Block]</link:label>
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerTextBlock_label_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RevenueFromContractWithCustomerTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax_ccb83cfb-d37c-4c7b-a52c-b2cba37ba2cc_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AdditionalPaidInCapitalMember_b34f138f-ad85-48d8-bc7f-4ef5b31a39fe_terseLabel_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Additional Paid-in Capital</link:label>
    <link:label id="lab_us-gaap_AdditionalPaidInCapitalMember_label_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Additional Paid-in Capital [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdditionalPaidInCapitalMember" xlink:to="lab_us-gaap_AdditionalPaidInCapitalMember" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentAnnualReport_4b216bd3-5186-49b6-a5dd-94163d09cb36_terseLabel_en-US" xlink:label="lab_dei_DocumentAnnualReport" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Annual Report</link:label>
    <link:label id="lab_dei_DocumentAnnualReport_label_en-US" xlink:label="lab_dei_DocumentAnnualReport" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Annual Report</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentAnnualReport" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentAnnualReport"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentAnnualReport" xlink:to="lab_dei_DocumentAnnualReport" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivables30To59DaysPastDueMember_c03c361f-3386-461f-8c47-a1aef34c840e_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivables30To59DaysPastDueMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Assets, 30 to 59 Days Past Due [Member]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivables30To59DaysPastDueMember_label_en-US" xlink:label="lab_us-gaap_FinancingReceivables30To59DaysPastDueMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Asset, 30 to 59 Days Past Due [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivables30To59DaysPastDueMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember" xlink:to="lab_us-gaap_FinancingReceivables30To59DaysPastDueMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary_0892e6b1-c94c-4858-ba91-e94c26d22ed7_terseLabel_en-US" xlink:label="lab_isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income before income tax benefit and equity in undistributed earnings of subsidiaries</link:label>
    <link:label id="lab_isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary_label_en-US" xlink:label="lab_isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) Before Income Taxes and Equity in Undistributed Net Income of Subsidiary</link:label>
    <link:label id="lab_isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary_documentation_en-US" xlink:label="lab_isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Income (Loss) Before Income Taxes and Equity in Undistributed Net Income of Subsidiary</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary" xlink:href="isba-20231231.xsd#isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary" xlink:to="lab_isba_IncomeLossBeforeIncomeTaxesandEquityinUndistributedNetIncomeofSubsidiary" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesInvestments_82bde627-0569-4152-a5eb-a34f13b7798e_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesInvestments" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accretion on securities</link:label>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesInvestments_label_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesInvestments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Investments</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesInvestments" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxLiabilitiesInvestments"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesInvestments" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesInvestments" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_CoverAbstract_label_en-US" xlink:label="lab_dei_CoverAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cover [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CoverAbstract" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_CoverAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_CoverAbstract" xlink:to="lab_dei_CoverAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubsequentEventsTextBlock_8ceb7d99-1db0-4c3d-878c-58365bf2c8ea_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventsTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subsequent Events [Text Block]</link:label>
    <link:label id="lab_us-gaap_SubsequentEventsTextBlock_label_en-US" xlink:label="lab_us-gaap_SubsequentEventsTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Events [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventsTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubsequentEventsTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsTextBlock" xlink:to="lab_us-gaap_SubsequentEventsTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AmortizationOfFinancingCosts_18154587-b20c-498f-a228-7581d0224d9a_terseLabel_en-US" xlink:label="lab_us-gaap_AmortizationOfFinancingCosts" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization of Debt Issuance Costs</link:label>
    <link:label id="lab_us-gaap_AmortizationOfFinancingCosts_label_en-US" xlink:label="lab_us-gaap_AmortizationOfFinancingCosts" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amortization of Debt Issuance Costs</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AmortizationOfFinancingCosts"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AmortizationOfFinancingCosts" xlink:to="lab_us-gaap_AmortizationOfFinancingCosts" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueMeasurementsRecurringMember_269ee9fd-0ab6-41c7-a069-7b7d4e25544f_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsRecurringMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Recurring items [Member]</link:label>
    <link:label id="lab_us-gaap_FairValueMeasurementsRecurringMember_label_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsRecurringMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Recurring [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementsRecurringMember" xlink:to="lab_us-gaap_FairValueMeasurementsRecurringMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_f3c63ec1-2dbd-41fe-80fa-e1c599b23038_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Measurements Inputs and Valuation Techniques [Line Items]</link:label>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems_label_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Measurement Inputs and Valuation Techniques [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems" xlink:to="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CompensationAndEmployeeBenefitPlansTextBlock_4c81d112-556e-4dd4-8687-d9f1b2142cfb_verboseLabel_en-US" xlink:label="lab_us-gaap_CompensationAndEmployeeBenefitPlansTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Benefit Plans</link:label>
    <link:label id="lab_us-gaap_CompensationAndEmployeeBenefitPlansTextBlock_label_en-US" xlink:label="lab_us-gaap_CompensationAndEmployeeBenefitPlansTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Compensation and Employee Benefit Plans [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CompensationAndEmployeeBenefitPlansTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CompensationAndEmployeeBenefitPlansTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CompensationAndEmployeeBenefitPlansTextBlock" xlink:to="lab_us-gaap_CompensationAndEmployeeBenefitPlansTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneLeverageCapitalAbstract_3e3a6818-c56b-4aed-b0d6-f3bbe0ec986e_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Tier 1 capital to average assets</link:label>
    <link:label id="lab_us-gaap_TierOneLeverageCapitalAbstract_label_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Leverage Capital [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneLeverageCapitalAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneLeverageCapitalAbstract" xlink:to="lab_us-gaap_TierOneLeverageCapitalAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue_39643e04-44e4-4668-9f11-ed35c69ec6c1_negatedLabel_en-US" xlink:label="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Common stock repurchased pursuant to publicly announced repurchase plan</link:label>
    <link:label id="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue_label_en-US" xlink:label="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Repurchased During Period, Excluding Stock For Deferred Compensation Obligations, Value</link:label>
    <link:label id="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue_documentation_en-US" xlink:label="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock Repurchased During Period, Excluding Stock For Deferred Compensation Obligations, Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue" xlink:href="isba-20231231.xsd#isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue" xlink:to="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SegmentReportingDisclosureTextBlock_4a693f82-01eb-4f8c-8c7c-e496334c5af9_verboseLabel_en-US" xlink:label="lab_us-gaap_SegmentReportingDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Operating Segments</link:label>
    <link:label id="lab_us-gaap_SegmentReportingDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_SegmentReportingDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SegmentReportingDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingDisclosureTextBlock" xlink:to="lab_us-gaap_SegmentReportingDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableTerm_5a484f3e-1c1f-4018-97b8-f13cb8995c01_verboseLabel_en-US" xlink:label="lab_isba_FinancingReceivableTerm" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Financing receivable, amortization term</link:label>
    <link:label id="lab_isba_FinancingReceivableTerm_label_en-US" xlink:label="lab_isba_FinancingReceivableTerm" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Term</link:label>
    <link:label id="lab_isba_FinancingReceivableTerm_documentation_en-US" xlink:label="lab_isba_FinancingReceivableTerm" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable, Term</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableTerm" xlink:href="isba-20231231.xsd#isba_FinancingReceivableTerm"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableTerm" xlink:to="lab_isba_FinancingReceivableTerm" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_b08bc84e-5739-451b-b779-33495c94667d_totalLabel_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Increase (decrease) in cash and cash equivalents</link:label>
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_label_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EquityComponentDomain_85131991-c4f6-4c44-b1d9-8af317ede37e_terseLabel_en-US" xlink:label="lab_us-gaap_EquityComponentDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity Component [Domain]</link:label>
    <link:label id="lab_us-gaap_EquityComponentDomain_label_en-US" xlink:label="lab_us-gaap_EquityComponentDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Component [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EquityComponentDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityComponentDomain" xlink:to="lab_us-gaap_EquityComponentDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_MortgageBackedSecuritiesOtherMember_4a2117c0-1369-46d5-aaa8-f9836a263947_terseLabel_en-US" xlink:label="lab_us-gaap_MortgageBackedSecuritiesOtherMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Mortgage Backed Securities, Other [Member]</link:label>
    <link:label id="lab_us-gaap_MortgageBackedSecuritiesOtherMember_label_en-US" xlink:label="lab_us-gaap_MortgageBackedSecuritiesOtherMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Mortgage-Backed Securities, Other [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesOtherMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MortgageBackedSecuritiesOtherMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MortgageBackedSecuritiesOtherMember" xlink:to="lab_us-gaap_MortgageBackedSecuritiesOtherMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostBasisRollingMaturityAbstract_4251d837-baec-4bad-9932-e8f16de1cb58_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostBasisRollingMaturityAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Maturity, Amortized Cost, Rolling Maturity [Abstract]</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostBasisRollingMaturityAbstract_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostBasisRollingMaturityAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Amortized Cost, Rolling Maturity [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostBasisRollingMaturityAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostBasisRollingMaturityAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostBasisRollingMaturityAbstract" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostBasisRollingMaturityAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialAssetsServicingOfFinancialAssetsPolicy_6a09f8e4-8252-48cf-b5cb-dd83fda4ab25_verboseLabel_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialAssetsServicingOfFinancialAssetsPolicy" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">SERVICING</link:label>
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialAssetsServicingOfFinancialAssetsPolicy_label_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialAssetsServicingOfFinancialAssetsPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Transfers and Servicing of Financial Assets, Servicing of Financial Assets, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialAssetsServicingOfFinancialAssetsPolicy" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TransfersAndServicingOfFinancialAssetsServicingOfFinancialAssetsPolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialAssetsServicingOfFinancialAssetsPolicy" xlink:to="lab_us-gaap_TransfersAndServicingOfFinancialAssetsServicingOfFinancialAssetsPolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesOther_d027be13-b056-4964-9658-77cc1e7a990f_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesOther" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesOther_label_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesOther" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Other</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesOther" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxLiabilitiesOther"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesOther" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesOther" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityCurrentReportingStatus_09fb584d-ab3b-43de-be47-9cbb387c9247_terseLabel_en-US" xlink:label="lab_dei_EntityCurrentReportingStatus" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Current Reporting Status</link:label>
    <link:label id="lab_dei_EntityCurrentReportingStatus_label_en-US" xlink:label="lab_dei_EntityCurrentReportingStatus" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Current Reporting Status</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCurrentReportingStatus" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityCurrentReportingStatus"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCurrentReportingStatus" xlink:to="lab_dei_EntityCurrentReportingStatus" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ConcentrationRiskTypeDomain_bed0ba6a-7a06-4299-8edf-a306686eeb5f_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskTypeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Domain]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskTypeDomain_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskTypeDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskTypeDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain" xlink:to="lab_us-gaap_ConcentrationRiskTypeDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DeferredTaxLiabilitiesPrepaidPensionCost_6e1625ea-2026-45a8-8a06-a79a2d73ef44_verboseLabel_en-US" xlink:label="lab_isba_DeferredTaxLiabilitiesPrepaidPensionCost" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Prepaid pension cost</link:label>
    <link:label id="lab_isba_DeferredTaxLiabilitiesPrepaidPensionCost_label_en-US" xlink:label="lab_isba_DeferredTaxLiabilitiesPrepaidPensionCost" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Prepaid Pension Cost</link:label>
    <link:label id="lab_isba_DeferredTaxLiabilitiesPrepaidPensionCost_documentation_en-US" xlink:label="lab_isba_DeferredTaxLiabilitiesPrepaidPensionCost" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Prepaid Pension Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DeferredTaxLiabilitiesPrepaidPensionCost" xlink:href="isba-20231231.xsd#isba_DeferredTaxLiabilitiesPrepaidPensionCost"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DeferredTaxLiabilitiesPrepaidPensionCost" xlink:to="lab_isba_DeferredTaxLiabilitiesPrepaidPensionCost" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount_fed285ab-2b5d-488f-8651-5e9ef2329bb4_negatedTerseLabel_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Interest income on tax exempt municipal securities</link:label>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount_label_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Exempt Income, Municipal Securities, Amount</link:label>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount_documentation_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Exempt Income, Municipal Securities, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount" xlink:href="isba-20231231.xsd#isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount" xlink:to="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeMunicipalSecuritiesAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsMember_83f074b3-0819-4e2d-b86f-eb13979618b3_verboseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Short-term investments [Member]</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsMember_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsMember" xlink:to="lab_us-gaap_CashAndCashEquivalentsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredIncomeTaxLiabilities_07807289-8802-4b3e-ad5f-73aca173e70e_totalLabel_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxLiabilities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total deferred tax liabilities</link:label>
    <link:label id="lab_us-gaap_DeferredIncomeTaxLiabilities_label_en-US" xlink:label="lab_us-gaap_DeferredIncomeTaxLiabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Gross</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredIncomeTaxLiabilities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities" xlink:to="lab_us-gaap_DeferredIncomeTaxLiabilities" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_ConsolidatedEntitiesDomain_812300c0-b123-44c9-9cc8-7978996b0634_terseLabel_en-US" xlink:label="lab_srt_ConsolidatedEntitiesDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consolidated Entities [Domain]</link:label>
    <link:label id="lab_srt_ConsolidatedEntitiesDomain_label_en-US" xlink:label="lab_srt_ConsolidatedEntitiesDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consolidated Entities [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ConsolidatedEntitiesDomain" xlink:to="lab_srt_ConsolidatedEntitiesDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubordinatedDebt_2b1996b6-a551-4c9f-98ce-a51b4c34c75f_terseLabel_en-US" xlink:label="lab_us-gaap_SubordinatedDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subordinated Debt</link:label>
    <link:label id="lab_us-gaap_SubordinatedDebt_label_en-US" xlink:label="lab_us-gaap_SubordinatedDebt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subordinated Debt</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubordinatedDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubordinatedDebt"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubordinatedDebt" xlink:to="lab_us-gaap_SubordinatedDebt" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure_ee32d7e1-6476-47e4-b6e8-0209c2f5c2f9_terseLabel_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank Borrowings, Fair Value Disclosure</link:label>
    <link:label id="lab_us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure_label_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank Borrowings, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure" xlink:to="lab_us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearFive_94d0cfe9-5fc9-470b-9755-f3deb1f8958d_verboseLabel_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearFive" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year Five</link:label>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearFive_label_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearFive" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Time Deposit Maturities, Year Five</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearFive" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TimeDepositMaturitiesYearFive"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimeDepositMaturitiesYearFive" xlink:to="lab_us-gaap_TimeDepositMaturitiesYearFive" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_VulnerableRatingMember_109a1574-f452-416d-b441-b71fcab57d10_terseLabel_en-US" xlink:label="lab_isba_VulnerableRatingMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Vulnerable Rating [Member]</link:label>
    <link:label id="lab_isba_VulnerableRatingMember_label_en-US" xlink:label="lab_isba_VulnerableRatingMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Vulnerable Rating [Member]</link:label>
    <link:label id="lab_isba_VulnerableRatingMember_documentation_en-US" xlink:label="lab_isba_VulnerableRatingMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Vulnerable rating.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_VulnerableRatingMember" xlink:href="isba-20231231.xsd#isba_VulnerableRatingMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_VulnerableRatingMember" xlink:to="lab_isba_VulnerableRatingMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember_4875310c-564b-486f-bb66-971633ead9b4_verboseLabel_en-US" xlink:label="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Estimated Fair Value [Member]</link:label>
    <link:label id="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember_label_en-US" xlink:label="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Estimate of Fair Value Measurement [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:to="lab_us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral_382621a4-a0d0-49a5-ab28-4619153f1b93_totalLabel_en-US" xlink:label="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:label id="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral_label_en-US" xlink:label="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pledged Financial Instruments, Not Separately Reported, Securities And Loans Receivable Pledged As Collateral</link:label>
    <link:label id="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral_documentation_en-US" xlink:label="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pledged Financial Instruments, Not Separately Reported, Securities And Loans Receivable Pledged As Collateral</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral" xlink:href="isba-20231231.xsd#isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral" xlink:to="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivablePledgedAsCollateral" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_1dbdcf75-fa11-4586-8833-21e7d5fb2da0_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">PREMISES AND EQUIPMENT</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PropertyPlantAndEquipmentPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredCompensationShareBasedPaymentsMember_ab973443-a7e4-4980-87fc-cbe7bcfc9d58_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredCompensationShareBasedPaymentsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Shares to be Issued for Deferred Compensation Obligations</link:label>
    <link:label id="lab_us-gaap_DeferredCompensationShareBasedPaymentsMember_label_en-US" xlink:label="lab_us-gaap_DeferredCompensationShareBasedPaymentsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation, Share-Based Payments [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCompensationShareBasedPaymentsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredCompensationShareBasedPaymentsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCompensationShareBasedPaymentsMember" xlink:to="lab_us-gaap_DeferredCompensationShareBasedPaymentsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_MortgageBackedSecuritiesMember_2db00dfa-427a-4fc4-9ab1-f9b8264d68b8_verboseLabel_en-US" xlink:label="lab_us-gaap_MortgageBackedSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Mortgage-backed securities [Member]</link:label>
    <link:label id="lab_us-gaap_MortgageBackedSecuritiesMember_d5da8110-39de-4bdd-ade7-7900c4aa2e15_terseLabel_en-US" xlink:label="lab_us-gaap_MortgageBackedSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Collateralized Mortgage Backed Securities [Member]</link:label>
    <link:label id="lab_us-gaap_MortgageBackedSecuritiesMember_label_en-US" xlink:label="lab_us-gaap_MortgageBackedSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Collateralized Mortgage-Backed Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_MortgageBackedSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MortgageBackedSecuritiesMember" xlink:to="lab_us-gaap_MortgageBackedSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations_888de727-224b-432f-9dbb-ca0da2b2b279_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subordinated Debt Obligations, Fair Value Disclosure</link:label>
    <link:label id="lab_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations_label_en-US" xlink:label="lab_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subordinated Debt Obligations, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations" xlink:to="lab_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FairValueMeasurementPolicyAbstract_9700a6f5-0992-496c-bb0a-6d1f5315fbdb_terseLabel_en-US" xlink:label="lab_isba_FairValueMeasurementPolicyAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Measurement, Policy [Abstract]</link:label>
    <link:label id="lab_isba_FairValueMeasurementPolicyAbstract_label_en-US" xlink:label="lab_isba_FairValueMeasurementPolicyAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Measurement, Policy [Abstract]</link:label>
    <link:label id="lab_isba_FairValueMeasurementPolicyAbstract_documentation_en-US" xlink:label="lab_isba_FairValueMeasurementPolicyAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Fair Value Measurement, Policy [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FairValueMeasurementPolicyAbstract" xlink:href="isba-20231231.xsd#isba_FairValueMeasurementPolicyAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FairValueMeasurementPolicyAbstract" xlink:to="lab_isba_FairValueMeasurementPolicyAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks_4dac1bbb-7bb6-4b8e-8221-5f5280d13c66_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Loans from Federal Home Loan Banks</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Loans from Federal Home Loan Banks</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks" xlink:to="lab_us-gaap_IncreaseDecreaseInLoansFromOtherFederalHomeLoanBanks" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations_db875cfa-6adf-400f-a046-c73b454c5b23_negatedLabel_en-US" xlink:label="lab_isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Common stock purchased for deferred compensation obligations</link:label>
    <link:label id="lab_isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations_label_en-US" xlink:label="lab_isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments for Repurchase of Common Stock for Deferred Compensation Obligations</link:label>
    <link:label id="lab_isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations_documentation_en-US" xlink:label="lab_isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Common stock purchased for deferred compensation obligations.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations" xlink:href="isba-20231231.xsd#isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations" xlink:to="lab_isba_PaymentsForRepurchaseOfCommonStockForDeferredCompensationObligations" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_ConsolidatedEntitiesAxis_359300b8-fb1e-4c48-b21b-157cff3d67e5_terseLabel_en-US" xlink:label="lab_srt_ConsolidatedEntitiesAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consolidated Entities [Axis]</link:label>
    <link:label id="lab_srt_ConsolidatedEntitiesAxis_label_en-US" xlink:label="lab_srt_ConsolidatedEntitiesAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consolidated Entities [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ConsolidatedEntitiesAxis" xlink:to="lab_srt_ConsolidatedEntitiesAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityVoluntaryFilers_fe8fa285-c41c-46e2-946c-a4e608f398a9_terseLabel_en-US" xlink:label="lab_dei_EntityVoluntaryFilers" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Voluntary Filers</link:label>
    <link:label id="lab_dei_EntityVoluntaryFilers_label_en-US" xlink:label="lab_dei_EntityVoluntaryFilers" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Voluntary Filers</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityVoluntaryFilers" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityVoluntaryFilers"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityVoluntaryFilers" xlink:to="lab_dei_EntityVoluntaryFilers" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_RangeMember_69d2925f-824e-4471-ad5a-292e6e6964f8_terseLabel_en-US" xlink:label="lab_srt_RangeMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statistical Measurement [Domain]</link:label>
    <link:label id="lab_srt_RangeMember_label_en-US" xlink:label="lab_srt_RangeMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statistical Measurement [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_RangeMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RangeMember" xlink:to="lab_srt_RangeMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableAllowance_1c414e1f-37a5-4f11-bb5b-966b34256b17_verboseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableAllowance" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Less allowance for loan losses</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableAllowance_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableAllowance" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Allowance</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableAllowance" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableAllowance"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableAllowance" xlink:to="lab_us-gaap_LoansAndLeasesReceivableAllowance" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_45b7c90e-6a55-4eb9-b385-89e4716ec741_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_02f8c817-b493-4b19-aee2-862dcf653688_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Beginning balance (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_6ae7fab3-7618-4f82-a3d7-2f637ab97a1e_periodEndLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Ending balance (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized_cc539f35-66c2-47b7-a8c2-08cdb9e88c00_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount</link:label>
    <link:label id="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized_label_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Leverage Capital, Well Capitalized, Minimum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized" xlink:to="lab_us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtDisclosureTextBlock_502c0d20-9d1d-4d74-a833-1b41d096d374_verboseLabel_en-US" xlink:label="lab_us-gaap_DebtDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Borrowed Funds</link:label>
    <link:label id="lab_us-gaap_DebtDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_DebtDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtDisclosureTextBlock" xlink:to="lab_us-gaap_DebtDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StatementOfStockholdersEquityAbstract_9d3b4bf2-18f2-464a-84ef-2626b687063c_terseLabel_en-US" xlink:label="lab_us-gaap_StatementOfStockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statement of Stockholders' Equity [Abstract]</link:label>
    <link:label id="lab_us-gaap_StatementOfStockholdersEquityAbstract_label_en-US" xlink:label="lab_us-gaap_StatementOfStockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Stockholders' Equity [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfStockholdersEquityAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementOfStockholdersEquityAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfStockholdersEquityAbstract" xlink:to="lab_us-gaap_StatementOfStockholdersEquityAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_12b0c682-64a7-44ab-a297-97d2729a3cc8_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investments, Debt and Equity Securities [Abstract]</link:label>
    <link:label id="lab_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract_label_en-US" xlink:label="lab_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investments, Debt and Equity Securities [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:to="lab_us-gaap_InvestmentsDebtAndEquitySecuritiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SegmentReportingAbstract_b62b4087-6540-4a9e-a60a-0576eb1b8e21_terseLabel_en-US" xlink:label="lab_us-gaap_SegmentReportingAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Segment Reporting [Abstract]</link:label>
    <link:label id="lab_us-gaap_SegmentReportingAbstract_label_en-US" xlink:label="lab_us-gaap_SegmentReportingAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SegmentReportingAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingAbstract" xlink:to="lab_us-gaap_SegmentReportingAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CorporateDebtSecuritiesMember_4284e78e-adb0-4724-8ba5-f655032c875b_terseLabel_en-US" xlink:label="lab_us-gaap_CorporateDebtSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Corporate Debt Securities</link:label>
    <link:label id="lab_us-gaap_CorporateDebtSecuritiesMember_label_en-US" xlink:label="lab_us-gaap_CorporateDebtSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Corporate Debt Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateDebtSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CorporateDebtSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CorporateDebtSecuritiesMember" xlink:to="lab_us-gaap_CorporateDebtSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_326822cd-5e7c-4771-8917-7a7a19d3d047_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal statutory tax rate</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod_4821fdf4-623e-41e7-8e3e-26e78fd60f81_negatedTerseLabel_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Vested</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod_label_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested in Period</link:label>
    <link:label id="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod_documentation_en-US" xlink:label="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested in Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod" xlink:href="isba-20231231.xsd#isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod" xlink:to="lab_isba_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueVestedInPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CompanyOwnedLifeInsurancePolicyTextBlock_fbc00b62-23c3-43d9-b2ae-6b1ae8e2302e_verboseLabel_en-US" xlink:label="lab_isba_CompanyOwnedLifeInsurancePolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">CORPORATE OWNED LIFE INSURANCE</link:label>
    <link:label id="lab_isba_CompanyOwnedLifeInsurancePolicyTextBlock_label_en-US" xlink:label="lab_isba_CompanyOwnedLifeInsurancePolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Company Owned Life Insurance [Policy Text Block]</link:label>
    <link:label id="lab_isba_CompanyOwnedLifeInsurancePolicyTextBlock_documentation_en-US" xlink:label="lab_isba_CompanyOwnedLifeInsurancePolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Company owned life insurance.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CompanyOwnedLifeInsurancePolicyTextBlock" xlink:href="isba-20231231.xsd#isba_CompanyOwnedLifeInsurancePolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CompanyOwnedLifeInsurancePolicyTextBlock" xlink:to="lab_isba_CompanyOwnedLifeInsurancePolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfCommonStock_9093ea23-0ce4-492d-8d64-7b2a7a1fd109_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from issuance of common stock</link:label>
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfCommonStock_b41b5511-cabd-4795-8328-6cb980da4ab2_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from the issuance of common stock</link:label>
    <link:label id="lab_us-gaap_ProceedsFromIssuanceOfCommonStock_label_en-US" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Issuance of Common Stock</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_EquityMethodAndOtherInvestmentsFairValueDisclosure_5c5f84c0-e8c6-4bfe-8b22-972a8f9fd4ae_verboseLabel_en-US" xlink:label="lab_isba_EquityMethodAndOtherInvestmentsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Equity securities without readily determinable fair values</link:label>
    <link:label id="lab_isba_EquityMethodAndOtherInvestmentsFairValueDisclosure_label_en-US" xlink:label="lab_isba_EquityMethodAndOtherInvestmentsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Method And Other Investments, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_EquityMethodAndOtherInvestmentsFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_EquityMethodAndOtherInvestmentsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Method And Other Investments, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_EquityMethodAndOtherInvestmentsFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_EquityMethodAndOtherInvestmentsFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_EquityMethodAndOtherInvestmentsFairValueDisclosure" xlink:to="lab_isba_EquityMethodAndOtherInvestmentsFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear_6ab1e7c9-80c5-4d4a-a4c4-15042ebd2e9b_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear" xlink:to="lab_us-gaap_FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeTaxDisclosureTextBlock_a35151d3-29c6-449b-a067-5f7bcb7bc240_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Federal Income Taxes</link:label>
    <link:label id="lab_us-gaap_IncomeTaxDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxDisclosureTextBlock" xlink:to="lab_us-gaap_IncomeTaxDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsSalesPolicy_d895079d-9f73-4332-bf9c-174fe0c110ec_verboseLabel_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsSalesPolicy" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">TRANSFERS OF FINANCIAL ASSETS</link:label>
    <link:label id="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsSalesPolicy_label_en-US" xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsSalesPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Transfers and Servicing of Financial Assets, Transfers of Financial Assets, Sales, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsSalesPolicy" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsSalesPolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsSalesPolicy" xlink:to="lab_us-gaap_TransfersAndServicingOfFinancialAssetsTransfersOfFinancialAssetsSalesPolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_94d977e8-f642-4c54-af7d-42303d5be9df_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year Five</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Five</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_IsabellaBankFoundationMember_0ad8ee62-5453-49e4-b603-33a505216d3a_verboseLabel_en-US" xlink:label="lab_isba_IsabellaBankFoundationMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Isabella Bank Foundation [Member]</link:label>
    <link:label id="lab_isba_IsabellaBankFoundationMember_0e6ff0fa-3040-4aea-8ecd-0a78826433af_terseLabel_en-US" xlink:label="lab_isba_IsabellaBankFoundationMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Isabella Bank Foundation [Member]</link:label>
    <link:label id="lab_isba_IsabellaBankFoundationMember_label_en-US" xlink:label="lab_isba_IsabellaBankFoundationMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Isabella Bank Foundation [Member]</link:label>
    <link:label id="lab_isba_IsabellaBankFoundationMember_documentation_en-US" xlink:label="lab_isba_IsabellaBankFoundationMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Isabella bank foundation.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_IsabellaBankFoundationMember" xlink:href="isba-20231231.xsd#isba_IsabellaBankFoundationMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_IsabellaBankFoundationMember" xlink:to="lab_isba_IsabellaBankFoundationMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestExpenseSubordinatedNotesAndDebentures_515e9af5-71f6-4c0d-bca0-e1463f301936_terseLabel_en-US" xlink:label="lab_us-gaap_InterestExpenseSubordinatedNotesAndDebentures" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Expense, Subordinated Notes and Debentures</link:label>
    <link:label id="lab_us-gaap_InterestExpenseSubordinatedNotesAndDebentures_label_en-US" xlink:label="lab_us-gaap_InterestExpenseSubordinatedNotesAndDebentures" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense, Subordinated Notes and Debentures</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseSubordinatedNotesAndDebentures" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestExpenseSubordinatedNotesAndDebentures"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpenseSubordinatedNotesAndDebentures" xlink:to="lab_us-gaap_InterestExpenseSubordinatedNotesAndDebentures" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestExpenseFederalHomeLoanBankAndFederalReserveBankAdvancesLongTerm_dc1886de-d4dc-4116-87c1-b83b9a5be03b_terseLabel_en-US" xlink:label="lab_us-gaap_InterestExpenseFederalHomeLoanBankAndFederalReserveBankAdvancesLongTerm" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Expense, Federal Home Loan Bank and Federal Reserve Bank Advances, Long-term</link:label>
    <link:label id="lab_us-gaap_InterestExpenseFederalHomeLoanBankAndFederalReserveBankAdvancesLongTerm_label_en-US" xlink:label="lab_us-gaap_InterestExpenseFederalHomeLoanBankAndFederalReserveBankAdvancesLongTerm" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense, Federal Home Loan Bank and Federal Reserve Bank Advances, Long-Term</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseFederalHomeLoanBankAndFederalReserveBankAdvancesLongTerm" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestExpenseFederalHomeLoanBankAndFederalReserveBankAdvancesLongTerm"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpenseFederalHomeLoanBankAndFederalReserveBankAdvancesLongTerm" xlink:to="lab_us-gaap_InterestExpenseFederalHomeLoanBankAndFederalReserveBankAdvancesLongTerm" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProceedsFromLifeInsurancePolicies_9df62c79-4638-40df-87d1-c1a21c69c5e7_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromLifeInsurancePolicies" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from the redemption of corporate owned life insurance policies</link:label>
    <link:label id="lab_us-gaap_ProceedsFromLifeInsurancePolicies_label_en-US" xlink:label="lab_us-gaap_ProceedsFromLifeInsurancePolicies" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Life Insurance Policy</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromLifeInsurancePolicies" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromLifeInsurancePolicies"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromLifeInsurancePolicies" xlink:to="lab_us-gaap_ProceedsFromLifeInsurancePolicies" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt_ee709beb-6d6e-4f33-97c2-3086bfe7c5f4_verboseLabel_en-US" xlink:label="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Nontaxable</link:label>
    <link:label id="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt_label_en-US" xlink:label="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest And Dividend Income, Securities, Operating, Available-for-sale, Tax Exempt</link:label>
    <link:label id="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt_documentation_en-US" xlink:label="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Interest And Dividend Income, Securities, Operating, Available-for-sale, Tax Exempt</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt" xlink:href="isba-20231231.xsd#isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt" xlink:to="lab_isba_InterestAndDividendIncomeSecuritiesOperatingAvailableforsaleTaxExempt" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RevenueRecognitionPolicyTextBlock_fa840ed1-6964-4d93-880a-ff103b74a93b_terseLabel_en-US" xlink:label="lab_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revenue Recognition, Policy [Policy Text Block]</link:label>
    <link:label id="lab_us-gaap_RevenueRecognitionPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RevenueRecognitionPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:to="lab_us-gaap_RevenueRecognitionPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommitmentMaturityPeriod_e0a65c3b-21c9-45be-92a8-38173054d1c1_verboseLabel_en-US" xlink:label="lab_isba_CommitmentMaturityPeriod" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum maturity period of commitments to extend credit</link:label>
    <link:label id="lab_isba_CommitmentMaturityPeriod_label_en-US" xlink:label="lab_isba_CommitmentMaturityPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitment, Maturity Period</link:label>
    <link:label id="lab_isba_CommitmentMaturityPeriod_documentation_en-US" xlink:label="lab_isba_CommitmentMaturityPeriod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Maximum maturity period of commitments to extend credit.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommitmentMaturityPeriod" xlink:href="isba-20231231.xsd#isba_CommitmentMaturityPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommitmentMaturityPeriod" xlink:to="lab_isba_CommitmentMaturityPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale_e78c43fd-9eb1-43b8-8136-fe84748a417c_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from loan sales</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale_01e56eb7-780a-4114-97b1-77cad9293b41_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from Sale of Mortgage Loans Held-for-sale</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale_label_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Sale, Loan, Mortgage, Held-for-Sale</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale" xlink:to="lab_us-gaap_ProceedsFromSaleOfMortgageLoansHeldForSale" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember_06f7c530-1751-418b-929c-b72a2b9a8426_terseLabel_en-US" xlink:label="lab_isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Principal Officers and Directors and Their Affiliates [Member]</link:label>
    <link:label id="lab_isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember_label_en-US" xlink:label="lab_isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Principal Officers and Directors and Their Affiliates [Member]</link:label>
    <link:label id="lab_isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember_documentation_en-US" xlink:label="lab_isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Principal Officers and Directors and Their Affiliates [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember" xlink:href="isba-20231231.xsd#isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember" xlink:to="lab_isba_PrincipalOfficersandDirectorsandTheirAffiliatesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_6fa36413-2eda-4d37-a3b4-1f5289ee8d83_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Measurements, Recurring and Nonrecurring [Table]</link:label>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_label_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Recurring and Nonrecurring [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_c154265b-5feb-482f-a8d8-9de8ddc17e5d_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Property, Plant and Equipment [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:to="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesTable_ba35d450-a35a-47cd-bd75-17e7e198ca26_terseLabel_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances [Table]</link:label>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesTable_label_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankAdvancesTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalHomeLoanBankAdvancesTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalHomeLoanBankAdvancesTable" xlink:to="lab_us-gaap_FederalHomeLoanBankAdvancesTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_d95b0820-b772-47d6-a775-c317029533bb_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair values of the Corporations pension plan assets by asset category</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Allocation of Plan Assets [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueInputsLevel3Member_17f3292b-1a3f-4688-baa0-b326d15cb6f3_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel3Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value, Inputs, Level 3 [Member]</link:label>
    <link:label id="lab_us-gaap_FairValueInputsLevel3Member_529268d0-a0b4-4eb1-a1cd-6990beb0d477_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel3Member" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Level 3 [Member]</link:label>
    <link:label id="lab_us-gaap_FairValueInputsLevel3Member_label_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel3Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Inputs, Level 3 [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel3Member" xlink:to="lab_us-gaap_FairValueInputsLevel3Member" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock_8ab67000-262b-4faf-93d5-37f6719e88b4_verboseLabel_en-US" xlink:label="lab_isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">EQUITY SECURITIES WITHOUT READILY DETERMINABLE FAIR VALUES</link:label>
    <link:label id="lab_isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock_label_en-US" xlink:label="lab_isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Method and Other Investments, Policy [Policy Text Block]</link:label>
    <link:label id="lab_isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock_documentation_en-US" xlink:label="lab_isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity securities without readily determinable fair values.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock" xlink:href="isba-20231231.xsd#isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock" xlink:to="lab_isba_EquityMethodandOtherInvestmentsPolicyPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CondensedCashFlowStatementTable_663caebb-4a4e-4aa3-9673-12ee25ac86b2_terseLabel_en-US" xlink:label="lab_srt_CondensedCashFlowStatementTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Condensed Cash Flow Statement [Table]</link:label>
    <link:label id="lab_srt_CondensedCashFlowStatementTable_label_en-US" xlink:label="lab_srt_CondensedCashFlowStatementTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Cash Flow Statement [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedCashFlowStatementTable" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CondensedCashFlowStatementTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CondensedCashFlowStatementTable" xlink:to="lab_srt_CondensedCashFlowStatementTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_07bbb051-4971-48b2-afc3-828654daa44d_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year One</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year One</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalHomeLoanBankStock_583b3702-1a4c-4dc6-afc5-3704ac5b638e_terseLabel_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankStock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">FHLB Stock</link:label>
    <link:label id="lab_us-gaap_FederalHomeLoanBankStock_label_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankStock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank Stock</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankStock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalHomeLoanBankStock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalHomeLoanBankStock" xlink:to="lab_us-gaap_FederalHomeLoanBankStock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_BuildingAndBuildingImprovementsMember_48117fac-1ef3-494c-a445-4fcf584fe2a8_verboseLabel_en-US" xlink:label="lab_us-gaap_BuildingAndBuildingImprovementsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Buildings and improvements [Member]</link:label>
    <link:label id="lab_us-gaap_BuildingAndBuildingImprovementsMember_label_en-US" xlink:label="lab_us-gaap_BuildingAndBuildingImprovementsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Building and Building Improvements [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BuildingAndBuildingImprovementsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_BuildingAndBuildingImprovementsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BuildingAndBuildingImprovementsMember" xlink:to="lab_us-gaap_BuildingAndBuildingImprovementsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestAndDividendIncomeOperatingAbstract_b66318fe-65e6-4d7c-9416-848a1712347b_verboseLabel_en-US" xlink:label="lab_us-gaap_InterestAndDividendIncomeOperatingAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interest income</link:label>
    <link:label id="lab_us-gaap_InterestAndDividendIncomeOperatingAbstract_label_en-US" xlink:label="lab_us-gaap_InterestAndDividendIncomeOperatingAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest and Dividend Income, Operating [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeOperatingAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestAndDividendIncomeOperatingAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestAndDividendIncomeOperatingAbstract" xlink:to="lab_us-gaap_InterestAndDividendIncomeOperatingAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds_28ea3689-3781-4600-9ee9-fded3f4e8151_negatedLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Repayments</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Related Parties, Proceeds</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds" xlink:to="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_ee18d97a-17f1-4de5-9efa-09b64a64f1f8_terseLabel_en-US" xlink:label="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Allowance for Credit Losses</link:label>
    <link:label id="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock_label_en-US" xlink:label="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Loss [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock" xlink:to="lab_us-gaap_AllowanceForCreditLossesOnFinancingReceivablesTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossTax_8d8e599d-8025-43bd-8ed0-5c246c984e52_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossTax" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Tax effect</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NetIncomeLoss_850c51ca-cd79-4c32-b4fb-27cd2e093468_totalLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">NET INCOME</link:label>
    <link:label id="lab_us-gaap_NetIncomeLoss_be4c6943-75f7-4067-aa21-95c3d6ca4a26_terseLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net Income (Loss) Attributable to Parent</link:label>
    <link:label id="lab_us-gaap_NetIncomeLoss_label_en-US" xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Income (Loss)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NetIncomeLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLoss" xlink:to="lab_us-gaap_NetIncomeLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DerivativeContractTypeDomain_a1492d96-a843-41db-88f8-49b216be531d_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeContractTypeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative Contract [Domain]</link:label>
    <link:label id="lab_us-gaap_DerivativeContractTypeDomain_label_en-US" xlink:label="lab_us-gaap_DerivativeContractTypeDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Contract [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeContractTypeDomain" xlink:to="lab_us-gaap_DerivativeContractTypeDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_e6c9760c-676e-4fd1-ba4a-482f32391636_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Asset, Equal to or Greater than 90 Days Past Due</link:label>
    <link:label id="lab_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_label_en-US" xlink:label="lab_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Asset, Equal to or Greater than 90 Days Past Due [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember" xlink:to="lab_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableAmountAdditionalApprovalThreshold_041cf7bb-8dab-48de-bb5e-c46444c0308b_verboseLabel_en-US" xlink:label="lab_isba_FinancingReceivableAmountAdditionalApprovalThreshold" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum amount without corporation approval</link:label>
    <link:label id="lab_isba_FinancingReceivableAmountAdditionalApprovalThreshold_label_en-US" xlink:label="lab_isba_FinancingReceivableAmountAdditionalApprovalThreshold" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Amount, Additional Approval Threshold</link:label>
    <link:label id="lab_isba_FinancingReceivableAmountAdditionalApprovalThreshold_documentation_en-US" xlink:label="lab_isba_FinancingReceivableAmountAdditionalApprovalThreshold" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable, Amount, Additional Approval Threshold</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableAmountAdditionalApprovalThreshold" xlink:href="isba-20231231.xsd#isba_FinancingReceivableAmountAdditionalApprovalThreshold"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableAmountAdditionalApprovalThreshold" xlink:to="lab_isba_FinancingReceivableAmountAdditionalApprovalThreshold" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract_dcbd54ed-b513-4b4f-a033-d5ae614ff90c_verboseLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">LIABILITIES AND SHAREHOLDERS' EQUITY</link:label>
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract_label_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities and Equity [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:to="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_c0bfa4d6-64dc-4eba-a7c9-db787ff81874_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets [Line Items]</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue_e13b23a8-8d9d-47ed-80f3-ec536702b8f3_terseLabel_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Market value, unissued</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue_label_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Common Stock Reserved for Future Issuance, Value</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue_documentation_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Common Stock Reserved for Future Issuance, Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue" xlink:href="isba-20231231.xsd#isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue" xlink:to="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockReservedforFutureIssuanceValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock_5025fcad-846a-4be4-99a3-166336f016b9_verboseLabel_en-US" xlink:label="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Parent Company Only Financial Information</link:label>
    <link:label id="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Financial Information of Parent Company Only Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:to="lab_us-gaap_CondensedFinancialInformationOfParentCompanyOnlyDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_a5cf969b-cf51-4bfc-94c5-3c4a5b5a26ff_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:to="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Goodwill_9661334f-c84e-4f71-bd9d-8e741f875a19_terseLabel_en-US" xlink:label="lab_us-gaap_Goodwill" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Goodwill</link:label>
    <link:label id="lab_us-gaap_Goodwill_label_en-US" xlink:label="lab_us-gaap_Goodwill" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Goodwill"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Goodwill" xlink:to="lab_us-gaap_Goodwill" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancialInstrumentPerformanceStatusDomain_07be38d9-b10d-492c-8b8a-845c379aaecc_terseLabel_en-US" xlink:label="lab_us-gaap_FinancialInstrumentPerformanceStatusDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Instrument Performance Status [Domain]</link:label>
    <link:label id="lab_us-gaap_FinancialInstrumentPerformanceStatusDomain_label_en-US" xlink:label="lab_us-gaap_FinancialInstrumentPerformanceStatusDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instrument Performance Status [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancialInstrumentPerformanceStatusDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialInstrumentPerformanceStatusDomain" xlink:to="lab_us-gaap_FinancialInstrumentPerformanceStatusDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueByMeasurementBasisAxis_0835a677-88b9-4fc6-b133-ac181978e19e_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByMeasurementBasisAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Measurement Basis [Axis]</link:label>
    <link:label id="lab_us-gaap_FairValueByMeasurementBasisAxis_label_en-US" xlink:label="lab_us-gaap_FairValueByMeasurementBasisAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Measurement Basis [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis" xlink:to="lab_us-gaap_FairValueByMeasurementBasisAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNoteTextBlock_5fb492bd-8044-4b60-a87d-a117cbfc784f_verboseLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNoteTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss)</link:label>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNoteTextBlock_label_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNoteTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Comprehensive Income (Loss) Note [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNoteTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ComprehensiveIncomeNoteTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNoteTextBlock" xlink:to="lab_us-gaap_ComprehensiveIncomeNoteTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LoansReceivableAllowanceFairValueDisclosure_333c0359-9bc7-4060-8930-5a4d37d0e487_verboseLabel_en-US" xlink:label="lab_isba_LoansReceivableAllowanceFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Less allowance for loan losses</link:label>
    <link:label id="lab_isba_LoansReceivableAllowanceFairValueDisclosure_label_en-US" xlink:label="lab_isba_LoansReceivableAllowanceFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable, Allowance, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_LoansReceivableAllowanceFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_LoansReceivableAllowanceFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Loans Receivable, Allowance, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LoansReceivableAllowanceFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_LoansReceivableAllowanceFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LoansReceivableAllowanceFairValueDisclosure" xlink:to="lab_isba_LoansReceivableAllowanceFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueDisclosureItemAmountsDomain_0ff6a6be-503c-48e1-9580-e6d1602bb423_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueDisclosureItemAmountsDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Measurement [Domain]</link:label>
    <link:label id="lab_us-gaap_FairValueDisclosureItemAmountsDomain_label_en-US" xlink:label="lab_us-gaap_FairValueDisclosureItemAmountsDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Measurement [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain" xlink:to="lab_us-gaap_FairValueDisclosureItemAmountsDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonEquityTierOneCapitalRatio_addc1fcb-0bd2-4464-913c-6281dbf497c1_terseLabel_en-US" xlink:label="lab_us-gaap_CommonEquityTierOneCapitalRatio" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Actual</link:label>
    <link:label id="lab_us-gaap_CommonEquityTierOneCapitalRatio_label_en-US" xlink:label="lab_us-gaap_CommonEquityTierOneCapitalRatio" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Actual</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonEquityTierOneCapitalRatio" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonEquityTierOneCapitalRatio"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonEquityTierOneCapitalRatio" xlink:to="lab_us-gaap_CommonEquityTierOneCapitalRatio" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_SubsidiariesMember_dafdeec7-c158-42e2-9142-70443496f4fc_verboseLabel_en-US" xlink:label="lab_srt_SubsidiariesMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Isabella Bank [Member]</link:label>
    <link:label id="lab_srt_SubsidiariesMember_label_en-US" xlink:label="lab_srt_SubsidiariesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsidiaries [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SubsidiariesMember" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_SubsidiariesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_SubsidiariesMember" xlink:to="lab_srt_SubsidiariesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CollateralAxis_d1caafe8-62d1-42a3-88da-6d43fea768e0_terseLabel_en-US" xlink:label="lab_us-gaap_CollateralAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Collateral Held [Axis]</link:label>
    <link:label id="lab_us-gaap_CollateralAxis_label_en-US" xlink:label="lab_us-gaap_CollateralAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Collateral Held [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CollateralAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CollateralAxis" xlink:to="lab_us-gaap_CollateralAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments_2d6c0623-9a99-47f6-b55a-b793cb20f69f_negatedTerseLabel_en-US" xlink:label="lab_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Impairments</link:label>
    <link:label id="lab_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments_46684c62-4d2b-45be-a801-1261a89be9ea_terseLabel_en-US" xlink:label="lab_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Real Estate, Foreclosed Assets, and Repossessed Assets, Valuation Adjustments</link:label>
    <link:label id="lab_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments_label_en-US" xlink:label="lab_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Real Estate, Foreclosed Assets, and Repossessed Assets, Valuation Adjustments</link:label>
    <link:label id="lab_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments_documentation_en-US" xlink:label="lab_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Real Estate, Foreclosed Assets, and Repossessed Assets, Valuation Adjustments</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments" xlink:href="isba-20231231.xsd#isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments" xlink:to="lab_isba_OtherRealEstateForeclosedAssetsandRepossessedAssetsValuationAdjustments" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember_1eac634d-9b90-449d-b4c3-d94554afa097_terseLabel_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">All Other AFS Securities [Member]</link:label>
    <link:label id="lab_isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember_label_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities, Excluding Auction Rate Money Market Preferred and Preferred Stocks [Member]</link:label>
    <link:label id="lab_isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember_documentation_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities, Excluding Auction Rate Money Market Preferred and Preferred Stocks [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember" xlink:href="isba-20231231.xsd#isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember" xlink:to="lab_isba_AvailableforsaleSecuritiesExcludingAuctionRateMoneyMarketPreferredandPreferredStocksMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock_9af54bb3-9e30-438d-9b23-4e685385dd0f_verboseLabel_en-US" xlink:label="lab_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Amortized cost and fair value of available-for-sale securities by contractual maturity</link:label>
    <link:label id="lab_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock_label_en-US" xlink:label="lab_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investments Classified by Contractual Maturity Date [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock" xlink:to="lab_us-gaap_InvestmentsClassifiedByContractualMaturityDateTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum_28c940a1-411e-4908-9f25-0905a1dd8b25_terseLabel_en-US" xlink:label="lab_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Well Capitalized, Minimum</link:label>
    <link:label id="lab_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum_label_en-US" xlink:label="lab_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Common Equity Tier 1 Risk-Based Capital Ratio, Well Capitalized, Minimum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum" xlink:to="lab_us-gaap_BankingRegulationCommonEquityTierOneRiskBasedCapitalRatioWellCapitalizedMinimum" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_4c6ab171-54dc-4276-85e9-f85aaef6c532_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Measurement Inputs and Valuation Techniques [Table]</link:label>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable_label_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Measurement Inputs and Valuation Techniques [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable" xlink:to="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentNameDomain_3abab72b-0bb1-4b30-bd5b-2fae7063898c_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentNameDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument, Name [Domain]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentNameDomain_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentNameDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Name [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentNameDomain" xlink:to="lab_us-gaap_DebtInstrumentNameDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_903e02db-2a5f-42e0-938f-af964f8034af_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Amounts reclassified from AOCI</link:label>
    <link:label id="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax_label_en-US" xlink:label="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax" xlink:to="lab_us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_e5aa1834-55b0-4a69-bf03-5b728eea0498_terseLabel_en-US" xlink:label="lab_isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_label_en-US" xlink:label="lab_isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_documentation_en-US" xlink:label="lab_isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:href="isba-20231231.xsd#isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:to="lab_isba_CapitalRequiredForCapitalAdequacyToRiskWeightedAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_985274f8-8a34-4cf5-bbd4-92fba9225e40_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Axis]</link:label>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis_label_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:to="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_138025fa-daf3-406a-a9a8-90aee1e30dae_verboseLabel_en-US" xlink:label="lab_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">ASSETS</link:label>
    <link:label id="lab_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract_label_en-US" xlink:label="lab_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract" xlink:to="lab_us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_5002fab7-85fc-4ab7-8d88-b30481bfa3f3_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet" xlink:to="lab_us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance_5eeb4702-c339-417e-85cf-2d2311040fec_verboseLabel_en-US" xlink:label="lab_isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Present value of the post retirement benefits payable</link:label>
    <link:label id="lab_isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance_label_en-US" xlink:label="lab_isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Portion Attributable to Employees Covered by Corporate Owned Life Insurance</link:label>
    <link:label id="lab_isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance_documentation_en-US" xlink:label="lab_isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Portion Attributable to Employees Covered by Corporate Owned Life Insurance</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance" xlink:href="isba-20231231.xsd#isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance" xlink:to="lab_isba_DefinedBenefitPlanPortionAttributabletoEmployeesCoveredbyCorporateOwnedLifeInsurance" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CapitalAbstract_c8595365-cbbc-4bad-b569-50be1d1f4a05_verboseLabel_en-US" xlink:label="lab_us-gaap_CapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total capital to risk weighted assets</link:label>
    <link:label id="lab_us-gaap_CapitalAbstract_label_en-US" xlink:label="lab_us-gaap_CapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Total Capital [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CapitalAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalAbstract" xlink:to="lab_us-gaap_CapitalAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableRevolvingWriteoff_b320a334-6d86-45ba-9e70-bcc8473739c6_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRevolvingWriteoff" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Revolving, Writeoff</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRevolvingWriteoff_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableRevolvingWriteoff" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Revolving, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRevolvingWriteoff" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableRevolvingWriteoff"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableRevolvingWriteoff" xlink:to="lab_us-gaap_FinancingReceivableRevolvingWriteoff" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward_6dccce44-bd00-4f1e-b1bc-6fb869a26ada_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Change in benefit obligation</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward" xlink:to="lab_us-gaap_DefinedBenefitPlanChangeInBenefitObligationRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapitalAbstract_11d3f0c8-489c-42bd-a859-abd89ca4dfc1_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Tier 1 capital to risk weighted assets</link:label>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapitalAbstract_label_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Risk-Based Capital [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneRiskBasedCapitalAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalAbstract" xlink:to="lab_us-gaap_TierOneRiskBasedCapitalAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_NoninterestIncomeInvestmentandTrustAdvisoryFees_894d0155-7c21-412e-9ee0-b95727e7ee51_terseLabel_en-US" xlink:label="lab_isba_NoninterestIncomeInvestmentandTrustAdvisoryFees" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Noninterest Income Investment and Trust Advisory Fees</link:label>
    <link:label id="lab_isba_NoninterestIncomeInvestmentandTrustAdvisoryFees_label_en-US" xlink:label="lab_isba_NoninterestIncomeInvestmentandTrustAdvisoryFees" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noninterest Income Investment and Trust Advisory Fees</link:label>
    <link:label id="lab_isba_NoninterestIncomeInvestmentandTrustAdvisoryFees_documentation_en-US" xlink:label="lab_isba_NoninterestIncomeInvestmentandTrustAdvisoryFees" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Noninterest Income Investment and Trust Advisory Fees</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_NoninterestIncomeInvestmentandTrustAdvisoryFees" xlink:href="isba-20231231.xsd#isba_NoninterestIncomeInvestmentandTrustAdvisoryFees"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_NoninterestIncomeInvestmentandTrustAdvisoryFees" xlink:to="lab_isba_NoninterestIncomeInvestmentandTrustAdvisoryFees" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_1b03fab5-4a66-4615-9e8b-87a9f13bda93_verboseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">CASH AND CASH EQUIVALENTS</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:to="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution_cc63ca85-545f-4450-9b6f-b7262ca0db63_verboseLabel_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Share based payment awards under equity compensation plan</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution_label_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Deferred Fees Contribution</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution_documentation_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share based payment awards under equity compensation plan.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution" xlink:href="isba-20231231.xsd#isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution" xlink:to="lab_isba_DeferredCompensationArrangementwithIndividualDeferredFeesContribution" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase_e9e747b9-b923-4f1e-b8fc-fd2bbadc5a7a_terseLabel_en-US" xlink:label="lab_us-gaap_InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Expense, Federal Funds Purchased and Securities Sold under Agreements to Repurchase</link:label>
    <link:label id="lab_us-gaap_InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase_label_en-US" xlink:label="lab_us-gaap_InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense, Federal Funds Purchased and Securities Sold under Agreements to Repurchase</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:to="lab_us-gaap_InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedContributionPlanTable_3d9904d0-846c-4038-8d91-503167f93e2b_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan [Table]</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanTable_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedContributionPlanTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanTable" xlink:to="lab_us-gaap_DefinedContributionPlanTable" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_InterestExpenseTimeDepositsGreaterthan250000_4ec6035c-408a-4541-b8b6-f3271ec8b1f5_terseLabel_en-US" xlink:label="lab_isba_InterestExpenseTimeDepositsGreaterthan250000" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Expense, Time Deposits, Greater than $250,000</link:label>
    <link:label id="lab_isba_InterestExpenseTimeDepositsGreaterthan250000_label_en-US" xlink:label="lab_isba_InterestExpenseTimeDepositsGreaterthan250000" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense, Time Deposits, Greater than $250,000</link:label>
    <link:label id="lab_isba_InterestExpenseTimeDepositsGreaterthan250000_documentation_en-US" xlink:label="lab_isba_InterestExpenseTimeDepositsGreaterthan250000" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Interest Expense, Time Deposits, Greater than $250,000</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_InterestExpenseTimeDepositsGreaterthan250000" xlink:href="isba-20231231.xsd#isba_InterestExpenseTimeDepositsGreaterthan250000"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_InterestExpenseTimeDepositsGreaterthan250000" xlink:to="lab_isba_InterestExpenseTimeDepositsGreaterthan250000" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueByBalanceSheetGroupingTextBlock_2b28dec0-5241-4155-a4e3-898e57bdb414_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueByBalanceSheetGroupingTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Carrying amount and estimated fair value of financial instruments not recorded at fair value</link:label>
    <link:label id="lab_us-gaap_FairValueByBalanceSheetGroupingTextBlock_label_en-US" xlink:label="lab_us-gaap_FairValueByBalanceSheetGroupingTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, by Balance Sheet Grouping [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByBalanceSheetGroupingTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueByBalanceSheetGroupingTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTextBlock" xlink:to="lab_us-gaap_FairValueByBalanceSheetGroupingTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_ProductsAndServicesDomain_f82fd2aa-b72c-4366-bd22-18b6751bd98a_terseLabel_en-US" xlink:label="lab_srt_ProductsAndServicesDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Product and Service [Domain]</link:label>
    <link:label id="lab_srt_ProductsAndServicesDomain_label_en-US" xlink:label="lab_srt_ProductsAndServicesDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product and Service [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ProductsAndServicesDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ProductsAndServicesDomain" xlink:to="lab_srt_ProductsAndServicesDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_f6434abe-14d7-4bf8-a88a-3f41c0347f8d_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Unrealized gains (losses), net of tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:to="lab_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueOptionChangesInFairValueGainLoss1_7bd0378c-11f1-43ac-8bc1-e305cfc295e1_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueOptionChangesInFairValueGainLoss1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Change in fair value recorded through earnings</link:label>
    <link:label id="lab_us-gaap_FairValueOptionChangesInFairValueGainLoss1_label_en-US" xlink:label="lab_us-gaap_FairValueOptionChangesInFairValueGainLoss1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Option, Changes in Fair Value, Gain (Loss)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueOptionChangesInFairValueGainLoss1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueOptionChangesInFairValueGainLoss1"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueOptionChangesInFairValueGainLoss1" xlink:to="lab_us-gaap_FairValueOptionChangesInFairValueGainLoss1" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StandbyLettersOfCreditMember_8affd731-c989-4768-a49d-7660548091f2_verboseLabel_en-US" xlink:label="lab_us-gaap_StandbyLettersOfCreditMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Commercial and standby letters of credit [Member]</link:label>
    <link:label id="lab_us-gaap_StandbyLettersOfCreditMember_label_en-US" xlink:label="lab_us-gaap_StandbyLettersOfCreditMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Standby Letters of Credit [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StandbyLettersOfCreditMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StandbyLettersOfCreditMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StandbyLettersOfCreditMember" xlink:to="lab_us-gaap_StandbyLettersOfCreditMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_40235532-0cda-48db-a7d0-02ddbbfaed1d_verboseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">INVESTING ACTIVITIES</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_1a8aa594-5d17-4f5d-921b-790e22c74640_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_7f691b2c-3509-4a07-9f25-93b2d7609cf5_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative Instruments and Hedging Activities Disclosure [Abstract]</link:label>
    <link:label id="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract_label_en-US" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Instruments and Hedging Activities Disclosure [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:to="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock_c65bb4f8-bd6a-432b-9952-d727a02f36a6_verboseLabel_en-US" xlink:label="lab_us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Minimum Regulatory Capital Requirements</link:label>
    <link:label id="lab_us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock_add4972e-b5b0-4e4e-9885-c067a0b53796_terseLabel_en-US" xlink:label="lab_us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Regulatory Capital Requirements under Banking Regulations [Text Block]</link:label>
    <link:label id="lab_us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock_label_en-US" xlink:label="lab_us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Regulatory Capital Requirements under Banking Regulations [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:to="lab_us-gaap_RegulatoryCapitalRequirementsUnderBankingRegulationsTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff_c211ca74-fe9e-493c-99db-30442e58ee5a_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff" xlink:to="lab_us-gaap_FinancingReceivableYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PlanNameDomain_703b82b9-d20e-4437-8f4c-a3a6ca369104_terseLabel_en-US" xlink:label="lab_us-gaap_PlanNameDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Plan Name [Domain]</link:label>
    <link:label id="lab_us-gaap_PlanNameDomain_label_en-US" xlink:label="lab_us-gaap_PlanNameDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Plan Name [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PlanNameDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanNameDomain" xlink:to="lab_us-gaap_PlanNameDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancialAssetPastDueMember_813950ea-a409-40e7-a11a-495896d9933f_terseLabel_en-US" xlink:label="lab_us-gaap_FinancialAssetPastDueMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Asset, Past Due</link:label>
    <link:label id="lab_us-gaap_FinancialAssetPastDueMember_label_en-US" xlink:label="lab_us-gaap_FinancialAssetPastDueMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Asset, Past Due [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetPastDueMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancialAssetPastDueMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialAssetPastDueMember" xlink:to="lab_us-gaap_FinancialAssetPastDueMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestExpense_e5d6101b-61e8-4702-be66-4b4ad2229571_totalLabel_en-US" xlink:label="lab_us-gaap_InterestExpense" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total interest expense</link:label>
    <link:label id="lab_us-gaap_InterestExpense_69104f1a-324b-49a7-a2a8-109be671a1bd_terseLabel_en-US" xlink:label="lab_us-gaap_InterestExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Expense</link:label>
    <link:label id="lab_us-gaap_InterestExpense_label_en-US" xlink:label="lab_us-gaap_InterestExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpense" xlink:to="lab_us-gaap_InterestExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_c2d6ff1c-7501-4f44-9a26-54774e4addf4_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unrecognized compensation expense</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy_cc666f2a-11e0-4f05-bc86-cc45b63fd01f_verboseLabel_en-US" xlink:label="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">LOANS</link:label>
    <link:label id="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy_label_en-US" xlink:label="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLoansAndLeasesReceivablePolicy" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinanceLoansAndLeasesReceivablePolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinanceLoansAndLeasesReceivablePolicy" xlink:to="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_UseOfEstimates_188d6414-0614-4471-9f07-ebdabc498a09_verboseLabel_en-US" xlink:label="lab_us-gaap_UseOfEstimates" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Use of Estimates</link:label>
    <link:label id="lab_us-gaap_UseOfEstimates_label_en-US" xlink:label="lab_us-gaap_UseOfEstimates" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Use of Estimates, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UseOfEstimates" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_UseOfEstimates"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UseOfEstimates" xlink:to="lab_us-gaap_UseOfEstimates" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfOtherOperatingCostAndExpenseByComponentTextBlock_363d8329-83d9-4f3a-a4d6-a1894fe0c727_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfOtherOperatingCostAndExpenseByComponentTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of expenses included in other noninterest expenses</link:label>
    <link:label id="lab_us-gaap_ScheduleOfOtherOperatingCostAndExpenseByComponentTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfOtherOperatingCostAndExpenseByComponentTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Other Operating Cost and Expense, by Component [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfOtherOperatingCostAndExpenseByComponentTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfOtherOperatingCostAndExpenseByComponentTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfOtherOperatingCostAndExpenseByComponentTextBlock" xlink:to="lab_us-gaap_ScheduleOfOtherOperatingCostAndExpenseByComponentTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesAbstract_eb318cfd-6e77-468a-99ca-be65e2f9949b_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">AFS Securities</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesAbstract_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesAbstract" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityFileNumber_ccd6951d-95e3-4ae3-a16f-1cb063188984_terseLabel_en-US" xlink:label="lab_dei_EntityFileNumber" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity File Number</link:label>
    <link:label id="lab_dei_EntityFileNumber_label_en-US" xlink:label="lab_dei_EntityFileNumber" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity File Number</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityFileNumber"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityFileNumber" xlink:to="lab_dei_EntityFileNumber" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableNonaccrualTable_558645da-aa6d-4027-9639-df81c3988d19_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableNonaccrualTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Nonaccrual [Table]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableNonaccrualTable_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableNonaccrualTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Nonaccrual [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableNonaccrualTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableNonaccrualTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableNonaccrualTable" xlink:to="lab_us-gaap_FinancingReceivableNonaccrualTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_9a615806-a110-4699-9dfb-4ca114dd2184_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unrealized Holding&#160;Gains (Losses) on AFS Securities [Member]</link:label>
    <link:label id="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_label_en-US" xlink:label="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:to="lab_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear_e8785e7c-a1c3-40ca-a247-6da01f4cdb15_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear" xlink:to="lab_us-gaap_FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearOne_f476ec9c-8a8f-4510-ba90-130dbc0edf73_terseLabel_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearOne" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Year One</link:label>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearOne_label_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearOne" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Time Deposit Maturities, Year One</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearOne" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TimeDepositMaturitiesYearOne"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimeDepositMaturitiesYearOne" xlink:to="lab_us-gaap_TimeDepositMaturitiesYearOne" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer_b3060293-f64d-4573-86e2-73d72bcd5b53_terseLabel_en-US" xlink:label="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Capital Adequacy Minimum with Buffer</link:label>
    <link:label id="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer_label_en-US" xlink:label="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer_documentation_en-US" xlink:label="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:href="isba-20231231.xsd#isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:to="lab_isba_TierOneRiskBasedCapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_AuditorFirmId_f1b90fc0-4170-4f96-82af-368d15194104_terseLabel_en-US" xlink:label="lab_dei_AuditorFirmId" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Auditor Firm ID</link:label>
    <link:label id="lab_dei_AuditorFirmId_label_en-US" xlink:label="lab_dei_AuditorFirmId" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Auditor Firm ID</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AuditorFirmId" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_AuditorFirmId"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_AuditorFirmId" xlink:to="lab_dei_AuditorFirmId" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AmortizationOfIntangibleAssets_1e0f6ad2-b621-48bd-8fc0-793aaa150068_verboseLabel_en-US" xlink:label="lab_us-gaap_AmortizationOfIntangibleAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Amortization of acquisition intangibles</link:label>
    <link:label id="lab_us-gaap_AmortizationOfIntangibleAssets_17fbca84-8c17-471a-8398-673a8cfea010_terseLabel_en-US" xlink:label="lab_us-gaap_AmortizationOfIntangibleAssets" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization expense of identifiable intangible assets</link:label>
    <link:label id="lab_us-gaap_AmortizationOfIntangibleAssets_label_en-US" xlink:label="lab_us-gaap_AmortizationOfIntangibleAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amortization of Intangible Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AmortizationOfIntangibleAssets" xlink:to="lab_us-gaap_AmortizationOfIntangibleAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityShellCompany_1cc6aadf-c4f7-4a22-a115-145b83b684ca_terseLabel_en-US" xlink:label="lab_dei_EntityShellCompany" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Shell Company</link:label>
    <link:label id="lab_dei_EntityShellCompany_label_en-US" xlink:label="lab_dei_EntityShellCompany" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Shell Company</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityShellCompany" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityShellCompany"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityShellCompany" xlink:to="lab_dei_EntityShellCompany" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansReceivableHeldForSaleAmount_044f0f2d-5758-4792-a250-9b78a6146172_terseLabel_en-US" xlink:label="lab_us-gaap_LoansReceivableHeldForSaleAmount" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans Receivable Held-for-sale, Amount</link:label>
    <link:label id="lab_us-gaap_LoansReceivableHeldForSaleAmount_label_en-US" xlink:label="lab_us-gaap_LoansReceivableHeldForSaleAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Held-for-Sale</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableHeldForSaleAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansReceivableHeldForSaleAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansReceivableHeldForSaleAmount" xlink:to="lab_us-gaap_LoansReceivableHeldForSaleAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DiscountedAppraisalValueValuationTechniqueMember_129b28f1-4798-4778-948e-f0d41ea234ba_verboseLabel_en-US" xlink:label="lab_isba_DiscountedAppraisalValueValuationTechniqueMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Discounted appraisal value [Member]</link:label>
    <link:label id="lab_isba_DiscountedAppraisalValueValuationTechniqueMember_label_en-US" xlink:label="lab_isba_DiscountedAppraisalValueValuationTechniqueMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Discounted Appraisal Value Valuation Technique [Member]</link:label>
    <link:label id="lab_isba_DiscountedAppraisalValueValuationTechniqueMember_documentation_en-US" xlink:label="lab_isba_DiscountedAppraisalValueValuationTechniqueMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Discounted Appraisal Value Valuation Technique [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DiscountedAppraisalValueValuationTechniqueMember" xlink:href="isba-20231231.xsd#isba_DiscountedAppraisalValueValuationTechniqueMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DiscountedAppraisalValueValuationTechniqueMember" xlink:to="lab_isba_DiscountedAppraisalValueValuationTechniqueMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_6f78be74-239c-4013-90fd-d19706dfbe7e_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Loss [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Loss [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable" xlink:to="lab_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_55abc802-a1c9-45de-aca3-2672a0ea2342_periodStartLabel_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Cash and cash equivalents at beginning of period</link:label>
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_e12364d8-702c-4682-8dc4-b4350a5fd286_periodEndLabel_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Cash and cash equivalents at end of period</link:label>
    <link:label id="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_label_en-US" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:to="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueByAssetClassAxis_50f3ede6-c5a0-4d60-acc2-75a6356e9d7d_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByAssetClassAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Asset Class [Axis]</link:label>
    <link:label id="lab_us-gaap_FairValueByAssetClassAxis_label_en-US" xlink:label="lab_us-gaap_FairValueByAssetClassAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Class [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByAssetClassAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueByAssetClassAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByAssetClassAxis" xlink:to="lab_us-gaap_FairValueByAssetClassAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities_7c30c609-fdc5-40e9-8073-e816cb6fdd9c_verboseLabel_en-US" xlink:label="lab_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accrued interest payable and other liabilities</link:label>
    <link:label id="lab_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities_a93fce2c-eaa9-49dd-8756-06d0de23766a_terseLabel_en-US" xlink:label="lab_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accrued interest and other liabilities</link:label>
    <link:label id="lab_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities_label_en-US" xlink:label="lab_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Interest Payable And Other Accrued Liabilities</link:label>
    <link:label id="lab_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities_documentation_en-US" xlink:label="lab_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Interest Payable And Other Accrued Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities" xlink:href="isba-20231231.xsd#isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities" xlink:to="lab_isba_IncreaseDecreaseinInterestPayableAndOtherAccruedLiabilities" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares_686d9a84-a02a-4f4f-99ee-6931d8ac1de8_negatedLabel_en-US" xlink:label="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Common stock repurchased pursuant to publicly announced repurchase plan, shares</link:label>
    <link:label id="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares_label_en-US" xlink:label="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Repurchased During Period, Excluding Stock For Deferred Compensation Obligations, Shares</link:label>
    <link:label id="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares_documentation_en-US" xlink:label="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock Repurchased During Period, Excluding Stock For Deferred Compensation Obligations, Shares</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares" xlink:href="isba-20231231.xsd#isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares" xlink:to="lab_isba_StockRepurchasedDuringPeriodExcludingStockForDeferredCompensationObligationsShares" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_1ae6a65c-30ea-4b60-81b1-e91c0959f72b_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonStockSharesIssued_7e8f690f-dd5a-462d-8bf3-468103cdf3a7_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesIssued" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares issued</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesIssued_label_en-US" xlink:label="lab_us-gaap_CommonStockSharesIssued" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares, Issued</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesIssued" xlink:to="lab_us-gaap_CommonStockSharesIssued" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_ebb1d436-32ec-4393-af69-bbfb306c7710_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accumulated other comprehensive income includes net unrecognized pension cost before income taxes</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xlink:to="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_0e46db5d-dbe2-4310-80d1-a8a6b82337cd_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Vested (in shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AssetsFairValueDisclosure_358134ba-2ee7-4d5b-9f0e-0b9b92e08530_verboseLabel_en-US" xlink:label="lab_us-gaap_AssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Fair value, total</link:label>
    <link:label id="lab_us-gaap_AssetsFairValueDisclosure_label_en-US" xlink:label="lab_us-gaap_AssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsFairValueDisclosure" xlink:to="lab_us-gaap_AssetsFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_e073eebb-e188-465e-905e-f4fad12944e8_totalLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total Unrealized Losses</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForSalePolicy_b51a7b47-65f8-4f1f-b68d-d80f4f6fecee_verboseLabel_en-US" xlink:label="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForSalePolicy" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">LOANS HELD FOR SALE</link:label>
    <link:label id="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForSalePolicy_label_en-US" xlink:label="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForSalePolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Held-for-Sale [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLoanAndLeaseReceivablesHeldForSalePolicy" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinanceLoanAndLeaseReceivablesHeldForSalePolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinanceLoanAndLeaseReceivablesHeldForSalePolicy" xlink:to="lab_us-gaap_FinanceLoanAndLeaseReceivablesHeldForSalePolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_57d94522-91c9-477b-bc6b-7474a4874167_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Corporation matching contribution, percent</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan, Employer Matching Contribution, Percent of Match</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch" xlink:to="lab_us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsToAcquireFederalReserveStock_b7f735ee-7104-4e40-be9e-ea88d2e2353a_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireFederalReserveStock" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Payments to Acquire Federal Reserve Bank Stock</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquireFederalReserveStock_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireFederalReserveStock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Federal Reserve Bank Stock</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireFederalReserveStock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsToAcquireFederalReserveStock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireFederalReserveStock" xlink:to="lab_us-gaap_PaymentsToAcquireFederalReserveStock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_38bc1eb5-53e6-47c9-8031-cfac87a73546_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unrecognized compensation expense, period for recognition</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTax_49de0bd8-b2a9-4bcc-b84e-8f6e55bfa57a_verboseLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTax" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Comprehensive income (loss)</link:label>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTax_a318df48-d43a-437f-99d9-9e3f37cddb59_totalLabel_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTax" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Comprehensive income (loss)</link:label>
    <link:label id="lab_us-gaap_ComprehensiveIncomeNetOfTax_label_en-US" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax" xlink:to="lab_us-gaap_ComprehensiveIncomeNetOfTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_8a1d9168-86b2-469c-9ab3-dfe828195025_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of Estimated future benefit payments</link:label>
    <link:label id="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Expected Benefit Payments [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_b6d3683a-1c6e-4820-8b37-33c28ebd839d_totalLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Deficiency in funded status at December31, included on the consolidated balance sheets in accrued interest payable and other liabilities</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Funded (Unfunded) Status of Plan</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanFundedStatusOfPlan"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:to="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityAddressAddressLine1_777ad7ce-af26-4cb5-a69c-5e978b083fce_terseLabel_en-US" xlink:label="lab_dei_EntityAddressAddressLine1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Address, Address Line One</link:label>
    <link:label id="lab_dei_EntityAddressAddressLine1_label_en-US" xlink:label="lab_dei_EntityAddressAddressLine1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Address, Address Line One</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityAddressAddressLine1"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressAddressLine1" xlink:to="lab_dei_EntityAddressAddressLine1" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption_a5b62503-90ff-4e8e-8c9d-678203bf322a_negatedTerseLabel_en-US" xlink:label="lab_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Bank Owned Life Insurance Income, From Policy Redemption</link:label>
    <link:label id="lab_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption_bc5753e4-7a0b-4a6e-9fee-4bb0322f6851_terseLabel_en-US" xlink:label="lab_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Bank Owned Life Insurance Income, From Policy Redemption</link:label>
    <link:label id="lab_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption_label_en-US" xlink:label="lab_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bank Owned Life Insurance Income, From Policy Redemption</link:label>
    <link:label id="lab_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption_documentation_en-US" xlink:label="lab_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Bank Owned Life Insurance Income, From Policy Redemption</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption" xlink:href="isba-20231231.xsd#isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption" xlink:to="lab_isba_BankOwnedLifeInsuranceIncomeFromPolicyRedemption" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue_01aec600-9f2c-441a-9430-8470288b058d_negatedLabel_en-US" xlink:label="lab_isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Common stock purchased for deferred compensation obligations</link:label>
    <link:label id="lab_isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue_label_en-US" xlink:label="lab_isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Repurchased During Period, For Deferred Compensation Obligations, Value</link:label>
    <link:label id="lab_isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue_documentation_en-US" xlink:label="lab_isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock Repurchased During Period, For Deferred Compensation Obligations, Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue" xlink:href="isba-20231231.xsd#isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue" xlink:to="lab_isba_StockRepurchasedDuringPeriodForDeferredCompensationObligationsValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_4754773f-fd8f-487b-b642-fa0a28a3caff_verboseLabel_en-US" xlink:label="lab_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">LIABILITIES</link:label>
    <link:label id="lab_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract_label_en-US" xlink:label="lab_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract" xlink:to="lab_us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansMember_80f965dc-8b79-454f-b414-2f85dbd305de_terseLabel_en-US" xlink:label="lab_us-gaap_LoansMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans</link:label>
    <link:label id="lab_us-gaap_LoansMember_label_en-US" xlink:label="lab_us-gaap_LoansMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansMember" xlink:to="lab_us-gaap_LoansMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_7fb3ffa3-4cd9-4561-ac10-4c4a2414f939_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]</link:label>
    <link:label id="lab_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems_label_en-US" xlink:label="lab_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems" xlink:to="lab_us-gaap_FairValueBalanceSheetGroupingFinancialStatementCaptionsLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Capital_c2825e24-db76-43c9-b9d3-f647a94ba78e_verboseLabel_en-US" xlink:label="lab_us-gaap_Capital" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Actual Amount</link:label>
    <link:label id="lab_us-gaap_Capital_label_en-US" xlink:label="lab_us-gaap_Capital" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Total Capital, Actual</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Capital" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Capital"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Capital" xlink:to="lab_us-gaap_Capital" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoanRestructuringModificationDomain_31990a6c-e816-4014-95e8-4204da7784e1_terseLabel_en-US" xlink:label="lab_us-gaap_LoanRestructuringModificationDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loan Restructuring Modification [Domain]</link:label>
    <link:label id="lab_us-gaap_LoanRestructuringModificationDomain_label_en-US" xlink:label="lab_us-gaap_LoanRestructuringModificationDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loan Restructuring Modification [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoanRestructuringModificationDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoanRestructuringModificationDomain" xlink:to="lab_us-gaap_LoanRestructuringModificationDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoanWriteoff_8e79976e-0f5e-4fbe-9be1-5968e2e4fb95_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoanWriteoff" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Revolving, Converted to Term Loan, Writeoff</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoanWriteoff_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoanWriteoff" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Revolving, Converted to Term Loan, Writeoff</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRevolvingConvertedToTermLoanWriteoff" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableRevolvingConvertedToTermLoanWriteoff"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableRevolvingConvertedToTermLoanWriteoff" xlink:to="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoanWriteoff" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_1124b1c2-8943-4caf-8d85-4d6211ba643f_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Summary of identifiable intangible assets</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Finite-Lived Intangible Assets [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeStatementAbstract_8a50012f-c156-43fe-a8c2-3ca9db2966f4_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeStatementAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Statement [Abstract]</link:label>
    <link:label id="lab_us-gaap_IncomeStatementAbstract_label_en-US" xlink:label="lab_us-gaap_IncomeStatementAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Statement [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeStatementAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="lab_us-gaap_IncomeStatementAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues_88247c45-7391-4325-bb5c-edacaf92fa88_verboseLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Issuance of common stock, shares</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Shares, New Issues</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ValuationTechniqueAxis_9041dcc5-270a-4084-93f7-0805d67f43c9_terseLabel_en-US" xlink:label="lab_us-gaap_ValuationTechniqueAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Valuation Approach and Technique [Axis]</link:label>
    <link:label id="lab_us-gaap_ValuationTechniqueAxis_label_en-US" xlink:label="lab_us-gaap_ValuationTechniqueAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Valuation Approach and Technique [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationTechniqueAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ValuationTechniqueAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationTechniqueAxis" xlink:to="lab_us-gaap_ValuationTechniqueAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_b3751aef-ae34-4fcd-955a-e70032ba2347_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Category [Axis]</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Category [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis" xlink:to="lab_us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsFairValueDisclosure_2ede0d5c-7dd9-4064-8bba-6ac3fa381291_terseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash and cash equivalents</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsFairValueDisclosure_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure" xlink:to="lab_us-gaap_CashAndCashEquivalentsFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentLineItems_165618a5-f0ff-4dd9-8459-512d0ce61d6e_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Credit Quality Indicators [Line Items]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentLineItems_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Credit Quality Indicator [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableRecordedInvestmentLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems" xlink:to="lab_us-gaap_FinancingReceivableRecordedInvestmentLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfForeclosedAssets_a199e1ab-9458-4e7b-bef9-e1aac86fd84e_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfForeclosedAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from sales of foreclosed assets</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfForeclosedAssets_label_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfForeclosedAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Sale of Foreclosed Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfForeclosedAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromSaleOfForeclosedAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleOfForeclosedAssets" xlink:to="lab_us-gaap_ProceedsFromSaleOfForeclosedAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_7ade0600-0b7a-4b3d-870f-a56d1968d1fe_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Income taxes at 34% statutory rate</link:label>
    <link:label id="lab_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_label_en-US" xlink:label="lab_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:to="lab_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_0235d6d3-f20f-410b-b397-990896d64b87_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets for Plan Benefits, Defined Benefit Plan</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets for Plan Benefits, Defined Benefit Plan</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent" xlink:to="lab_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtLongtermAndShorttermCombinedAmount_f624ad47-17e0-4c30-86b0-e265111af9a4_totalLabel_en-US" xlink:label="lab_us-gaap_DebtLongtermAndShorttermCombinedAmount" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Debt, Long-term and Short-term, Combined Amount</link:label>
    <link:label id="lab_us-gaap_DebtLongtermAndShorttermCombinedAmount_03cd38b3-76c1-4cda-8cd3-947618d30e61_terseLabel_en-US" xlink:label="lab_us-gaap_DebtLongtermAndShorttermCombinedAmount" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt, Long-term and Short-term, Combined Amount</link:label>
    <link:label id="lab_us-gaap_DebtLongtermAndShorttermCombinedAmount_label_en-US" xlink:label="lab_us-gaap_DebtLongtermAndShorttermCombinedAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt, Long-Term and Short-Term, Combined Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtLongtermAndShorttermCombinedAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtLongtermAndShorttermCombinedAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtLongtermAndShorttermCombinedAmount" xlink:to="lab_us-gaap_DebtLongtermAndShorttermCombinedAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax_28b7c8c7-205d-47aa-ac63-d0a6b589805d_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Change in unrecognized pension cost arising during the year</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeReclassificationAdjustmentsAndTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LandMember_3ed7c143-1057-47d1-8114-afd530a79f82_verboseLabel_en-US" xlink:label="lab_us-gaap_LandMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Land [Member]</link:label>
    <link:label id="lab_us-gaap_LandMember_label_en-US" xlink:label="lab_us-gaap_LandMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Land [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LandMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LandMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LandMember" xlink:to="lab_us-gaap_LandMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancialInstrumentAxis_6161d566-e0d4-4431-bab3-bf1dee6c7a40_terseLabel_en-US" xlink:label="lab_us-gaap_FinancialInstrumentAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Instrument [Axis]</link:label>
    <link:label id="lab_us-gaap_FinancialInstrumentAxis_label_en-US" xlink:label="lab_us-gaap_FinancialInstrumentAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instrument [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialInstrumentAxis" xlink:to="lab_us-gaap_FinancialInstrumentAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestReceivable_b5f5dd01-19c0-42b0-9941-c567f586d144_terseLabel_en-US" xlink:label="lab_us-gaap_InterestReceivable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Receivable</link:label>
    <link:label id="lab_us-gaap_InterestReceivable_label_en-US" xlink:label="lab_us-gaap_InterestReceivable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Receivable</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestReceivable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestReceivable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestReceivable" xlink:to="lab_us-gaap_InterestReceivable" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_InterestReceivableFairValueDisclosure_0f29f45b-c6a9-4dd8-b36f-598368567e41_verboseLabel_en-US" xlink:label="lab_isba_InterestReceivableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accrued interest receivable</link:label>
    <link:label id="lab_isba_InterestReceivableFairValueDisclosure_label_en-US" xlink:label="lab_isba_InterestReceivableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Receivable, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_InterestReceivableFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_InterestReceivableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Interest Receivable, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_InterestReceivableFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_InterestReceivableFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_InterestReceivableFairValueDisclosure" xlink:to="lab_isba_InterestReceivableFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract_610a4aa9-db65-41d8-b6cd-a58f7e1c6a07_verboseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Loans</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Net Amount [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract" xlink:to="lab_us-gaap_LoansAndLeasesReceivableNetReportedAmountAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityCommonStockSharesOutstanding_bfe73b06-02f8-4562-9f17-bb2dc7846684_terseLabel_en-US" xlink:label="lab_dei_EntityCommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Common Stock, Shares Outstanding</link:label>
    <link:label id="lab_dei_EntityCommonStockSharesOutstanding_label_en-US" xlink:label="lab_dei_EntityCommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Common Stock, Shares Outstanding</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCommonStockSharesOutstanding" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityCommonStockSharesOutstanding"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCommonStockSharesOutstanding" xlink:to="lab_dei_EntityCommonStockSharesOutstanding" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_ScheduleOfCondensedBalanceSheetTableTextBlock_7ee4be53-c733-4f59-abc7-e64070b29af9_verboseLabel_en-US" xlink:label="lab_srt_ScheduleOfCondensedBalanceSheetTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interim Condensed Balance Sheets</link:label>
    <link:label id="lab_srt_ScheduleOfCondensedBalanceSheetTableTextBlock_label_en-US" xlink:label="lab_srt_ScheduleOfCondensedBalanceSheetTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Balance Sheet [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfCondensedBalanceSheetTableTextBlock" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ScheduleOfCondensedBalanceSheetTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ScheduleOfCondensedBalanceSheetTableTextBlock" xlink:to="lab_srt_ScheduleOfCondensedBalanceSheetTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FixedIncomeFundsMember_cd684da0-d472-4089-8f86-e2f1c9ff47f6_verboseLabel_en-US" xlink:label="lab_us-gaap_FixedIncomeFundsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Fixed income [Member]</link:label>
    <link:label id="lab_us-gaap_FixedIncomeFundsMember_eecc2b99-02ce-4f64-8332-22ca057352d1_terseLabel_en-US" xlink:label="lab_us-gaap_FixedIncomeFundsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fixed Income Funds [Member]</link:label>
    <link:label id="lab_us-gaap_FixedIncomeFundsMember_label_en-US" xlink:label="lab_us-gaap_FixedIncomeFundsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fixed Income Funds [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FixedIncomeFundsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FixedIncomeFundsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FixedIncomeFundsMember" xlink:to="lab_us-gaap_FixedIncomeFundsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableModificationsLineItems_4b0ea1c9-2f6b-4be7-a3f6-5273fcb7f524_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableModificationsLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Troubled Debt Restructuring [Line Items]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableModificationsLineItems_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableModificationsLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Modified [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModificationsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableModificationsLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems" xlink:to="lab_us-gaap_FinancingReceivableModificationsLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis_a32d37b4-eddd-483a-89e6-841cc766dead_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Hierarchy and NAV [Axis]</link:label>
    <link:label id="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis_label_en-US" xlink:label="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Hierarchy and NAV [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearFour_c895e915-352f-4d41-b5a0-968dc46aff06_verboseLabel_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearFour" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year Four</link:label>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearFour_label_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearFour" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Time Deposit Maturities, Year Four</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearFour" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TimeDepositMaturitiesYearFour"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimeDepositMaturitiesYearFour" xlink:to="lab_us-gaap_TimeDepositMaturitiesYearFour" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RetainedEarningsAccumulatedDeficit_34168abe-0fcc-476b-98c9-bbdfc21db858_verboseLabel_en-US" xlink:label="lab_us-gaap_RetainedEarningsAccumulatedDeficit" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Retained earnings</link:label>
    <link:label id="lab_us-gaap_RetainedEarningsAccumulatedDeficit_label_en-US" xlink:label="lab_us-gaap_RetainedEarningsAccumulatedDeficit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retained Earnings (Accumulated Deficit)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetainedEarningsAccumulatedDeficit" xlink:to="lab_us-gaap_RetainedEarningsAccumulatedDeficit" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CollateralDomain_e38e51e7-fdf5-4508-a797-0188d056c123_terseLabel_en-US" xlink:label="lab_us-gaap_CollateralDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Collateral Held [Domain]</link:label>
    <link:label id="lab_us-gaap_CollateralDomain_label_en-US" xlink:label="lab_us-gaap_CollateralDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Collateral Held [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CollateralDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CollateralDomain" xlink:to="lab_us-gaap_CollateralDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentFaceAmount_b34f3590-136b-4408-85f9-28f22202a1fa_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument, Face Amount</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentFaceAmount_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Face Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentFaceAmount" xlink:to="lab_us-gaap_DebtInstrumentFaceAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityAddressStateOrProvince_a9c709c1-7c34-424f-b106-569d202a2197_terseLabel_en-US" xlink:label="lab_dei_EntityAddressStateOrProvince" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Address, State or Province</link:label>
    <link:label id="lab_dei_EntityAddressStateOrProvince_label_en-US" xlink:label="lab_dei_EntityAddressStateOrProvince" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Address, State or Province</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityAddressStateOrProvince"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressStateOrProvince" xlink:to="lab_dei_EntityAddressStateOrProvince" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_MembershipsAndSubscriptionsExpense_2dba7466-c1c2-43c9-8c02-f35b60d05568_terseLabel_en-US" xlink:label="lab_isba_MembershipsAndSubscriptionsExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Memberships and Subscriptions Expense</link:label>
    <link:label id="lab_isba_MembershipsAndSubscriptionsExpense_label_en-US" xlink:label="lab_isba_MembershipsAndSubscriptionsExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Memberships and Subscriptions Expense</link:label>
    <link:label id="lab_isba_MembershipsAndSubscriptionsExpense_documentation_en-US" xlink:label="lab_isba_MembershipsAndSubscriptionsExpense" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Memberships and Subscriptions Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_MembershipsAndSubscriptionsExpense" xlink:href="isba-20231231.xsd#isba_MembershipsAndSubscriptionsExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_MembershipsAndSubscriptionsExpense" xlink:to="lab_isba_MembershipsAndSubscriptionsExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_bdfee97f-158f-4f2b-a70b-a3d2c509d762_verboseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">OPERATING ACTIVITIES</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_62cc9df0-0292-4a7d-bd24-f50136b0b9d5_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_5d1e683c-f797-4591-841c-4ed17fb3b40b_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maturities, calls, and principal payments</link:label>
    <link:label id="lab_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities_label_en-US" xlink:label="lab_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities" xlink:to="lab_us-gaap_ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NoninterestIncomeAbstract_86b11dd6-7dec-4320-a488-0f63482c8db6_verboseLabel_en-US" xlink:label="lab_us-gaap_NoninterestIncomeAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Noninterest income</link:label>
    <link:label id="lab_us-gaap_NoninterestIncomeAbstract_label_en-US" xlink:label="lab_us-gaap_NoninterestIncomeAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noninterest Income [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestIncomeAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoninterestIncomeAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoninterestIncomeAbstract" xlink:to="lab_us-gaap_NoninterestIncomeAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_2b0ed72f-b326-4089-b92f-171deeb6aad9_terseLabel_en-US" xlink:label="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_label_en-US" xlink:label="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer_documentation_en-US" xlink:label="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:href="isba-20231231.xsd#isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:to="lab_isba_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssetsMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_ScheduleOfCondensedIncomeStatementTableTextBlock_e64b5e91-9926-481f-9530-e73347e0d7ef_verboseLabel_en-US" xlink:label="lab_srt_ScheduleOfCondensedIncomeStatementTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interim Condensed Statements of Income</link:label>
    <link:label id="lab_srt_ScheduleOfCondensedIncomeStatementTableTextBlock_label_en-US" xlink:label="lab_srt_ScheduleOfCondensedIncomeStatementTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Income Statement [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfCondensedIncomeStatementTableTextBlock" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ScheduleOfCondensedIncomeStatementTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ScheduleOfCondensedIncomeStatementTableTextBlock" xlink:to="lab_srt_ScheduleOfCondensedIncomeStatementTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_8d1bd4cf-62b3-4c34-bb9d-b01a3a0c3f49_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss) [Line Items]</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_label_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss) [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract_b53669d3-4604-4f41-a0e0-c3db66d3f728_verboseLabel_en-US" xlink:label="lab_us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">AFS securities</link:label>
    <link:label id="lab_us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract_label_en-US" xlink:label="lab_us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest and Dividend Income, Securities, by Taxable Status [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract" xlink:to="lab_us-gaap_InterestAndDividendIncomeSecuritiesByTaxableStatusAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_d7507586-d5fe-40c0-8379-967f0beb335e_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Asset Class [Domain]</link:label>
    <link:label id="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_label_en-US" xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Class [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:to="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount_7261c111-b544-4d6a-9405-9941f685d25c_negatedTerseLabel_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Earnings on corporate owned life insurance policies</link:label>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount_label_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Exempt Income, Corporate Owned Life Insurance, Amount</link:label>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount_documentation_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Exempt Income, Corporate Owned Life Insurance, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount" xlink:href="isba-20231231.xsd#isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount" xlink:to="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeCorporateOwnedLifeInsuranceAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent_d2ca8811-da5f-4028-a692-516c30e1b540_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Employees contribution</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent" xlink:to="lab_us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets_3558d8a9-140b-43ca-ac75-a211cc2d2bf8_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Actual Ratio</link:label>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets_label_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Risk-Based Capital Ratio, Actual</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets" xlink:to="lab_us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount_58e2d8b6-f757-4183-9f6c-6793e535d192_negatedLabel_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount_label_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Exempt Income, Other, Amount</link:label>
    <link:label id="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount_documentation_en-US" xlink:label="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Exempt Income, Other, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount" xlink:href="isba-20231231.xsd#isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount" xlink:to="lab_isba_EffectiveIncomeTaxRateReconciliationTaxExemptIncomeOtherAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable_270d957b-b4e8-4b0c-9e3b-69399c3cd5cb_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Fair Value, Off-balance Sheet Risks [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Fair Value, off-Balance-Sheet Risks [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable" xlink:to="lab_us-gaap_ScheduleOfFairValueOffBalanceSheetRisksTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock_e71cb255-83c9-4b4f-8a04-b47480e07a81_verboseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Details about accumulated other comprehensive income components</link:label>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:to="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableModificationPercentageOfPortfolioSegment_ae657421-8ba2-4c96-a30f-cd03a0de9e81_terseLabel_en-US" xlink:label="lab_isba_FinancingReceivableModificationPercentageOfPortfolioSegment" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable Modification Percentage of Portfolio Segment</link:label>
    <link:label id="lab_isba_FinancingReceivableModificationPercentageOfPortfolioSegment_label_en-US" xlink:label="lab_isba_FinancingReceivableModificationPercentageOfPortfolioSegment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable Modification Percentage of Portfolio Segment</link:label>
    <link:label id="lab_isba_FinancingReceivableModificationPercentageOfPortfolioSegment_documentation_en-US" xlink:label="lab_isba_FinancingReceivableModificationPercentageOfPortfolioSegment" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable Modification Percentage of Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableModificationPercentageOfPortfolioSegment" xlink:href="isba-20231231.xsd#isba_FinancingReceivableModificationPercentageOfPortfolioSegment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableModificationPercentageOfPortfolioSegment" xlink:to="lab_isba_FinancingReceivableModificationPercentageOfPortfolioSegment" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax_75a3c15e-c17d-4487-89bb-5d502209de43_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification adjustment for net periodic benefit cost included in net income</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DepositLiabilitiesCollateralIssuedFinancialInstruments_d7680d31-bd93-4439-a8ba-ab7771976001_terseLabel_en-US" xlink:label="lab_us-gaap_DepositLiabilitiesCollateralIssuedFinancialInstruments" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deposit Liabilities, Collateral Issued, Financial Instruments</link:label>
    <link:label id="lab_us-gaap_DepositLiabilitiesCollateralIssuedFinancialInstruments_label_en-US" xlink:label="lab_us-gaap_DepositLiabilitiesCollateralIssuedFinancialInstruments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deposit Liabilities, Collateral Issued, Financial Instruments</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositLiabilitiesCollateralIssuedFinancialInstruments" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DepositLiabilitiesCollateralIssuedFinancialInstruments"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepositLiabilitiesCollateralIssuedFinancialInstruments" xlink:to="lab_us-gaap_DepositLiabilitiesCollateralIssuedFinancialInstruments" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax_c8ca8be0-d0ff-448e-a89b-0484eb11093b_verboseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Unrealized gains (losses) arising during the period</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment and Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LowSatisfactoryRatingMember_7ac5b8a6-537a-4f91-9924-6df0a5597ec4_terseLabel_en-US" xlink:label="lab_isba_LowSatisfactoryRatingMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Low Satisfactory Rating [Member]</link:label>
    <link:label id="lab_isba_LowSatisfactoryRatingMember_81b37906-6067-4bf5-a957-9afea45cc279_verboseLabel_en-US" xlink:label="lab_isba_LowSatisfactoryRatingMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">4 - Low satisfactory [Member]</link:label>
    <link:label id="lab_isba_LowSatisfactoryRatingMember_label_en-US" xlink:label="lab_isba_LowSatisfactoryRatingMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Low Satisfactory Rating [Member]</link:label>
    <link:label id="lab_isba_LowSatisfactoryRatingMember_documentation_en-US" xlink:label="lab_isba_LowSatisfactoryRatingMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Low satisfactory rating.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LowSatisfactoryRatingMember" xlink:href="isba-20231231.xsd#isba_LowSatisfactoryRatingMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LowSatisfactoryRatingMember" xlink:to="lab_isba_LowSatisfactoryRatingMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_19478b69-1ac8-42b7-be24-59d74a1b5ebe_terseLabel_en-US" xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Basis of Presentation</link:label>
    <link:label id="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:to="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_898b975a-0125-4ce3-8a7a-b6eddc80a481_verboseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss)</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_90be0f1d-4357-4949-865d-705699b2e292_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">AOCI Attributable to Parent [Member]</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember_label_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">AOCI Attributable to Parent [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedContributionPlanCostRecognized_ed8e7c1b-fbc1-4609-b501-8916f21b4ffe_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanCostRecognized" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Plan expenses</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanCostRecognized_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanCostRecognized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan, Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanCostRecognized" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedContributionPlanCostRecognized"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanCostRecognized" xlink:to="lab_us-gaap_DefinedContributionPlanCostRecognized" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis_5fd2c2f3-5dd9-48c1-9c01-dda36da3df49_verboseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maturing, After Five Years But Within Ten Years</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 5 through 10 Years, Amortized Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AuctionRateSecuritiesMember_a0c5cdc8-815e-4555-9f73-441f79a9cfd8_terseLabel_en-US" xlink:label="lab_us-gaap_AuctionRateSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Auction Rate Securities [Member]</link:label>
    <link:label id="lab_us-gaap_AuctionRateSecuritiesMember_b91be171-3952-4824-b379-20afb4ffaf17_verboseLabel_en-US" xlink:label="lab_us-gaap_AuctionRateSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Auction rate money market preferred [Member]</link:label>
    <link:label id="lab_us-gaap_AuctionRateSecuritiesMember_label_en-US" xlink:label="lab_us-gaap_AuctionRateSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Auction Rate Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AuctionRateSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AuctionRateSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AuctionRateSecuritiesMember" xlink:to="lab_us-gaap_AuctionRateSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_076027cc-d734-4453-82f5-6c0884d28085_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss) [Table]</link:label>
    <link:label id="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_label_en-US" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss) [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NoninterestExpense_36be864a-4139-47c5-b75c-65b77dd93381_totalLabel_en-US" xlink:label="lab_us-gaap_NoninterestExpense" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total noninterest expenses</link:label>
    <link:label id="lab_us-gaap_NoninterestExpense_label_en-US" xlink:label="lab_us-gaap_NoninterestExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noninterest Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoninterestExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoninterestExpense" xlink:to="lab_us-gaap_NoninterestExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TimeDeposits_161d2180-8933-4baf-bd2f-28369a8f69fd_totalLabel_en-US" xlink:label="lab_us-gaap_TimeDeposits" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Time Deposits, Total</link:label>
    <link:label id="lab_us-gaap_TimeDeposits_label_en-US" xlink:label="lab_us-gaap_TimeDeposits" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Time Deposits</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDeposits" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TimeDeposits"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimeDeposits" xlink:to="lab_us-gaap_TimeDeposits" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_27292a1c-0a2e-4c5d-9f98-1dfbd777d6d6_terseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Pension&#160;Plan [Member]</link:label>
    <link:label id="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_label_en-US" xlink:label="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:to="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PlanNameAxis_6d9dc342-7c1b-433f-8055-99e0c2691ff3_terseLabel_en-US" xlink:label="lab_us-gaap_PlanNameAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Plan Name [Axis]</link:label>
    <link:label id="lab_us-gaap_PlanNameAxis_label_en-US" xlink:label="lab_us-gaap_PlanNameAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Plan Name [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PlanNameAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanNameAxis" xlink:to="lab_us-gaap_PlanNameAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtDisclosureAbstract_e8ff349f-50ed-44f4-a5f6-77e246aac263_terseLabel_en-US" xlink:label="lab_us-gaap_DebtDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Disclosure [Abstract]</link:label>
    <link:label id="lab_us-gaap_DebtDisclosureAbstract_label_en-US" xlink:label="lab_us-gaap_DebtDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Disclosure [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtDisclosureAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtDisclosureAbstract" xlink:to="lab_us-gaap_DebtDisclosureAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebitCardMember_aa219549-d613-46f2-9276-28546ecfc496_terseLabel_en-US" xlink:label="lab_us-gaap_DebitCardMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debit Card [Member]</link:label>
    <link:label id="lab_us-gaap_DebitCardMember_label_en-US" xlink:label="lab_us-gaap_DebitCardMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debit Card [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebitCardMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebitCardMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebitCardMember" xlink:to="lab_us-gaap_DebitCardMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EarningsPerShareAbstract_fb3cef98-4d8e-490c-b622-20edab15d417_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Earnings per share</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareAbstract_3b2d1efa-8f6c-48db-b874-b4c99a4950cf_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Earnings Per Share [Abstract]</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareAbstract_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EarningsPerShareAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareAbstract" xlink:to="lab_us-gaap_EarningsPerShareAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ExcellentRatingMember_53714585-7655-4899-8487-39f0f9daa45b_terseLabel_en-US" xlink:label="lab_isba_ExcellentRatingMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">1 - Excellent [Member]</link:label>
    <link:label id="lab_isba_ExcellentRatingMember_label_en-US" xlink:label="lab_isba_ExcellentRatingMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Excellent Rating [Member]</link:label>
    <link:label id="lab_isba_ExcellentRatingMember_documentation_en-US" xlink:label="lab_isba_ExcellentRatingMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Excellent Rating [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ExcellentRatingMember" xlink:href="isba-20231231.xsd#isba_ExcellentRatingMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ExcellentRatingMember" xlink:to="lab_isba_ExcellentRatingMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonStockValue_c399aa08-832c-4f8b-8241-f315562ac866_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockValue" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock &#8212; no par value 15,000,000 shares authorized</link:label>
    <link:label id="lab_us-gaap_CommonStockValue_label_en-US" xlink:label="lab_us-gaap_CommonStockValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Value, Issued</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockValue" xlink:to="lab_us-gaap_CommonStockValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommercialRealEstateMember_c1ab1b69-390d-49b6-baea-6a4fee2d763d_terseLabel_en-US" xlink:label="lab_us-gaap_CommercialRealEstateMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial Real Estate</link:label>
    <link:label id="lab_us-gaap_CommercialRealEstateMember_label_en-US" xlink:label="lab_us-gaap_CommercialRealEstateMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Real Estate [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialRealEstateMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommercialRealEstateMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommercialRealEstateMember" xlink:to="lab_us-gaap_CommercialRealEstateMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss_defba40f-da12-49fa-b9d8-ab31a31359f1_verboseLabel_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Applicable income tax expense</link:label>
    <link:label id="lab_isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss_label_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities, Income Tax Expense (Benefit) On Realized Gain (Loss)</link:label>
    <link:label id="lab_isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss_documentation_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities, Income Tax Expense (Benefit) On Realized Gain (Loss)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss" xlink:href="isba-20231231.xsd#isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss" xlink:to="lab_isba_AvailableforsaleSecuritiesIncomeTaxExpenseBenefitOnRealizedGainLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_UnusedLinesOfCreditMember_2ba1e775-b0a0-471b-bfdd-7192ff4842e0_verboseLabel_en-US" xlink:label="lab_us-gaap_UnusedLinesOfCreditMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Unfunded commitments under lines of credit [Member]</link:label>
    <link:label id="lab_us-gaap_UnusedLinesOfCreditMember_label_en-US" xlink:label="lab_us-gaap_UnusedLinesOfCreditMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unused lines of Credit [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnusedLinesOfCreditMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_UnusedLinesOfCreditMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnusedLinesOfCreditMember" xlink:to="lab_us-gaap_UnusedLinesOfCreditMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent_522af0f4-d3db-4a15-8325-284fefd9bef5_negatedTotalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="resource" xml:lang="en-US">Net change in unrecognized actuarial loss and prior service cost</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent_e2157e9c-9dd6-4438-b842-3606fc429d05_negatedLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net change in unrecognized actuarial loss and prior service cost</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, before Tax, after Reclassification Adjustment, Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent" xlink:to="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentBeforeTaxPortionAttributableToParent" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock_ea13381d-9653-4203-ab50-e2ee4d20c3a5_verboseLabel_en-US" xlink:label="lab_isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Scheduled maturities of time deposits</link:label>
    <link:label id="lab_isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock_label_en-US" xlink:label="lab_isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Scheduled Maturities of Time Deposits [Table Text Block]</link:label>
    <link:label id="lab_isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock_documentation_en-US" xlink:label="lab_isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Scheduled maturities of time deposits.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock" xlink:href="isba-20231231.xsd#isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock" xlink:to="lab_isba_ScheduledMaturitiesOfTimeDepositsTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_f5a18f3a-4a99-496b-b3e8-4b3694d07a69_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounting Standards Update and Change in Accounting Principle</link:label>
    <link:label id="lab_us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Standards Update and Change in Accounting Principle [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:to="lab_us-gaap_ScheduleOfNewAccountingPronouncementsAndChangesInAccountingPrinciplesTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_4a44b733-2668-4112-9cf9-e21775ab84d5_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Defined Benefit Plans Disclosures [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Defined Benefit Plans Disclosures [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:to="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerAbstract_984fe73c-8b88-447f-981c-0c0368d4d40a_terseLabel_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer [Abstract]</link:label>
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerAbstract_label_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RevenueFromContractWithCustomerAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerAbstract" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ShortTermDebtWeightedAverageInterestRates_c5ba6b24-5426-428d-b987-d0d88e87c8b1_verboseLabel_en-US" xlink:label="lab_isba_ShortTermDebtWeightedAverageInterestRates" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Interest Rate During the Period</link:label>
    <link:label id="lab_isba_ShortTermDebtWeightedAverageInterestRates_label_en-US" xlink:label="lab_isba_ShortTermDebtWeightedAverageInterestRates" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short Term Debt Weighted Average Interest Rates</link:label>
    <link:label id="lab_isba_ShortTermDebtWeightedAverageInterestRates_documentation_en-US" xlink:label="lab_isba_ShortTermDebtWeightedAverageInterestRates" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Short term debt weighted average interest rates.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ShortTermDebtWeightedAverageInterestRates" xlink:href="isba-20231231.xsd#isba_ShortTermDebtWeightedAverageInterestRates"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ShortTermDebtWeightedAverageInterestRates" xlink:to="lab_isba_ShortTermDebtWeightedAverageInterestRates" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityFilerCategory_4a085ff0-5a13-4325-a511-216661a29ea8_terseLabel_en-US" xlink:label="lab_dei_EntityFilerCategory" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Filer Category</link:label>
    <link:label id="lab_dei_EntityFilerCategory_label_en-US" xlink:label="lab_dei_EntityFilerCategory" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Filer Category</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFilerCategory" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityFilerCategory"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityFilerCategory" xlink:to="lab_dei_EntityFilerCategory" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StatementTable_e48fd838-628f-4087-80ca-0ac205c69ac1_terseLabel_en-US" xlink:label="lab_us-gaap_StatementTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statement [Table]</link:label>
    <link:label id="lab_us-gaap_StatementTable_label_en-US" xlink:label="lab_us-gaap_StatementTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementTable" xlink:to="lab_us-gaap_StatementTable" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_CurrentFiscalYearEndDate_adca3c2c-3b98-4fbc-b20f-ca5cb50c3233_terseLabel_en-US" xlink:label="lab_dei_CurrentFiscalYearEndDate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Current Fiscal Year End Date</link:label>
    <link:label id="lab_dei_CurrentFiscalYearEndDate_label_en-US" xlink:label="lab_dei_CurrentFiscalYearEndDate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current Fiscal Year End Date</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CurrentFiscalYearEndDate" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_CurrentFiscalYearEndDate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_CurrentFiscalYearEndDate" xlink:to="lab_dei_CurrentFiscalYearEndDate" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ImpairedFinancingReceivableFairValueDisclosure_bc306947-5ae2-4bc6-b735-180dc7bb9115_terseLabel_en-US" xlink:label="lab_isba_ImpairedFinancingReceivableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Impaired loans (net of the allowance for loan losses)</link:label>
    <link:label id="lab_isba_ImpairedFinancingReceivableFairValueDisclosure_label_en-US" xlink:label="lab_isba_ImpairedFinancingReceivableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Impaired Financing Receivable, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_ImpairedFinancingReceivableFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_ImpairedFinancingReceivableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Impaired Financing Receivable, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ImpairedFinancingReceivableFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_ImpairedFinancingReceivableFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ImpairedFinancingReceivableFairValueDisclosure" xlink:to="lab_isba_ImpairedFinancingReceivableFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_1b6b091e-8f7c-4d63-8cd6-9e4db01fc9cd_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of federal income tax expense</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DividendIncomeReceivedFromSubsidiary_465e17a4-bd0e-478d-b8de-b97209950fdb_verboseLabel_en-US" xlink:label="lab_isba_DividendIncomeReceivedFromSubsidiary" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Dividends from subsidiaries</link:label>
    <link:label id="lab_isba_DividendIncomeReceivedFromSubsidiary_label_en-US" xlink:label="lab_isba_DividendIncomeReceivedFromSubsidiary" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Dividend Income Received From Subsidiary</link:label>
    <link:label id="lab_isba_DividendIncomeReceivedFromSubsidiary_documentation_en-US" xlink:label="lab_isba_DividendIncomeReceivedFromSubsidiary" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Dividend Income Received From Subsidiary</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DividendIncomeReceivedFromSubsidiary" xlink:href="isba-20231231.xsd#isba_DividendIncomeReceivedFromSubsidiary"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DividendIncomeReceivedFromSubsidiary" xlink:to="lab_isba_DividendIncomeReceivedFromSubsidiary" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialRealEstateMultifamilyPortfolioSegmentMember_6e06da90-9135-4d33-88ff-b9a9786cf5ad_terseLabel_en-US" xlink:label="lab_isba_CommercialRealEstateMultifamilyPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, Multifamily, Portfolio Segment</link:label>
    <link:label id="lab_isba_CommercialRealEstateMultifamilyPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_CommercialRealEstateMultifamilyPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, Multifamily, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_CommercialRealEstateMultifamilyPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_CommercialRealEstateMultifamilyPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial Real Estate, Multifamily, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialRealEstateMultifamilyPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_CommercialRealEstateMultifamilyPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialRealEstateMultifamilyPortfolioSegmentMember" xlink:to="lab_isba_CommercialRealEstateMultifamilyPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_EquityCollectiveTrustMember_ca950adb-5e44-465e-a060-d28b39f4ef5d_verboseLabel_en-US" xlink:label="lab_isba_EquityCollectiveTrustMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Equity investments [Member]</link:label>
    <link:label id="lab_isba_EquityCollectiveTrustMember_f88cd549-c4de-41f8-8c5c-e4fd41f892fd_terseLabel_en-US" xlink:label="lab_isba_EquityCollectiveTrustMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity Collective Trust [Member]</link:label>
    <link:label id="lab_isba_EquityCollectiveTrustMember_label_en-US" xlink:label="lab_isba_EquityCollectiveTrustMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Collective Trust [Member]</link:label>
    <link:label id="lab_isba_EquityCollectiveTrustMember_documentation_en-US" xlink:label="lab_isba_EquityCollectiveTrustMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Collective Trust [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_EquityCollectiveTrustMember" xlink:href="isba-20231231.xsd#isba_EquityCollectiveTrustMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_EquityCollectiveTrustMember" xlink:to="lab_isba_EquityCollectiveTrustMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueByBalanceSheetGroupingTable_7b7fdc7d-88b7-415d-a9e4-31a7dad6b417_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueByBalanceSheetGroupingTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value, by Balance Sheet Grouping [Table]</link:label>
    <link:label id="lab_us-gaap_FairValueByBalanceSheetGroupingTable_label_en-US" xlink:label="lab_us-gaap_FairValueByBalanceSheetGroupingTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, by Balance Sheet Grouping [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByBalanceSheetGroupingTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueByBalanceSheetGroupingTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByBalanceSheetGroupingTable" xlink:to="lab_us-gaap_FairValueByBalanceSheetGroupingTable" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CondensedFinancialInformationOfParentCompanyOnlyDisclosureAbstract_645e6beb-ad8b-4f10-8f12-31d4f3c99809_terseLabel_en-US" xlink:label="lab_srt_CondensedFinancialInformationOfParentCompanyOnlyDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Condensed Financial Information Disclosure [Abstract]</link:label>
    <link:label id="lab_srt_CondensedFinancialInformationOfParentCompanyOnlyDisclosureAbstract_label_en-US" xlink:label="lab_srt_CondensedFinancialInformationOfParentCompanyOnlyDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Financial Information Disclosure [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedFinancialInformationOfParentCompanyOnlyDisclosureAbstract" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CondensedFinancialInformationOfParentCompanyOnlyDisclosureAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CondensedFinancialInformationOfParentCompanyOnlyDisclosureAbstract" xlink:to="lab_srt_CondensedFinancialInformationOfParentCompanyOnlyDisclosureAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_HighQualityRatingMember_9d0ca888-cf1d-4436-9e85-b6a61914da4e_terseLabel_en-US" xlink:label="lab_isba_HighQualityRatingMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">High Quality Rating [Member]</link:label>
    <link:label id="lab_isba_HighQualityRatingMember_label_en-US" xlink:label="lab_isba_HighQualityRatingMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Quality Rating [Member]</link:label>
    <link:label id="lab_isba_HighQualityRatingMember_documentation_en-US" xlink:label="lab_isba_HighQualityRatingMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High quality rating.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_HighQualityRatingMember" xlink:href="isba-20231231.xsd#isba_HighQualityRatingMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_HighQualityRatingMember" xlink:to="lab_isba_HighQualityRatingMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivablesTextBlock_a8f8a482-cc93-4a6a-997f-3e89188c0dcf_verboseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivablesTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Loans and ACL</link:label>
    <link:label id="lab_us-gaap_FinancingReceivablesTextBlock_label_en-US" xlink:label="lab_us-gaap_FinancingReceivablesTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivables [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivablesTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivablesTextBlock" xlink:to="lab_us-gaap_FinancingReceivablesTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_d89b3a55-a27c-4da9-a292-6b75ab50b039_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">After Five Years</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubordinatedBorrowingTable_b89f27f8-00c9-44e3-9ccf-50d131644cda_terseLabel_en-US" xlink:label="lab_us-gaap_SubordinatedBorrowingTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Subordinated Borrowing</link:label>
    <link:label id="lab_us-gaap_SubordinatedBorrowingTable_label_en-US" xlink:label="lab_us-gaap_SubordinatedBorrowingTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subordinated Borrowing [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubordinatedBorrowingTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubordinatedBorrowingTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubordinatedBorrowingTable" xlink:to="lab_us-gaap_SubordinatedBorrowingTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubordinatedBorrowingLineItems_2030a3a7-8efc-4ee8-9096-fff1933ab9d1_terseLabel_en-US" xlink:label="lab_us-gaap_SubordinatedBorrowingLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subordinated Borrowing [Line Items]</link:label>
    <link:label id="lab_us-gaap_SubordinatedBorrowingLineItems_label_en-US" xlink:label="lab_us-gaap_SubordinatedBorrowingLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subordinated Borrowing [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubordinatedBorrowingLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubordinatedBorrowingLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubordinatedBorrowingLineItems" xlink:to="lab_us-gaap_SubordinatedBorrowingLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeLossFromSubsidiariesNetOfTax_0ea52a87-ab4a-4808-b8b5-c5e7899fcb7f_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromSubsidiariesNetOfTax" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Undistributed earnings of subsidiaries</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromSubsidiariesNetOfTax_d4045c4c-1b9b-4468-9a11-10ba9a53fa7e_negatedLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromSubsidiariesNetOfTax" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Undistributed earnings of subsidiaries</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromSubsidiariesNetOfTax_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromSubsidiariesNetOfTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Subsidiaries, Net of Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromSubsidiariesNetOfTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeLossFromSubsidiariesNetOfTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromSubsidiariesNetOfTax" xlink:to="lab_us-gaap_IncomeLossFromSubsidiariesNetOfTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_9c848214-e1ad-4e44-88ee-2659c0900b6b_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Nonaccrual [Line Items]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Loss [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems" xlink:to="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueMeasurementsNonrecurringMember_def8324a-dccd-408a-ac9e-f94297b3fed3_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsNonrecurringMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Nonrecurring items [Member]</link:label>
    <link:label id="lab_us-gaap_FairValueMeasurementsNonrecurringMember_label_en-US" xlink:label="lab_us-gaap_FairValueMeasurementsNonrecurringMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Nonrecurring [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsNonrecurringMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueMeasurementsNonrecurringMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementsNonrecurringMember" xlink:to="lab_us-gaap_FairValueMeasurementsNonrecurringMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoan_5863e2db-8ba5-4ab8-a021-c7651aec8cd3_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoan" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Revolving, Converted to Term Loan</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoan_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoan" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Revolving, Converted to Term Loan</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRevolvingConvertedToTermLoan" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableRevolvingConvertedToTermLoan"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableRevolvingConvertedToTermLoan" xlink:to="lab_us-gaap_FinancingReceivableRevolvingConvertedToTermLoan" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherIncome_36f3617a-db1e-41e7-b4bb-2d10081d8747_terseLabel_en-US" xlink:label="lab_us-gaap_OtherIncome" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Income</link:label>
    <link:label id="lab_us-gaap_OtherIncome_label_en-US" xlink:label="lab_us-gaap_OtherIncome" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Income</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherIncome" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherIncome"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherIncome" xlink:to="lab_us-gaap_OtherIncome" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsToAcquireOtherInvestments_8ba06dcf-5491-4a61-8f66-abdc94a1da32_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireOtherInvestments" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Payments to Acquire Other Investments</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquireOtherInvestments_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireOtherInvestments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Other Investments</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireOtherInvestments" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsToAcquireOtherInvestments"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireOtherInvestments" xlink:to="lab_us-gaap_PaymentsToAcquireOtherInvestments" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions_e8c2cb29-1919-421a-8b76-3a90cb1a1c9e_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net unrecognized actuarial loss on pension plan</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Pensions</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions" xlink:to="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPensions" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NoninterestExpenseDirectorsFees_b1c937e3-ec17-4e93-a6a1-97c9c4fdd0b8_verboseLabel_en-US" xlink:label="lab_us-gaap_NoninterestExpenseDirectorsFees" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Director fees</link:label>
    <link:label id="lab_us-gaap_NoninterestExpenseDirectorsFees_3ca60dec-34ff-4aed-aa75-5f997521913a_terseLabel_en-US" xlink:label="lab_us-gaap_NoninterestExpenseDirectorsFees" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Noninterest Expense Directors Fees</link:label>
    <link:label id="lab_us-gaap_NoninterestExpenseDirectorsFees_label_en-US" xlink:label="lab_us-gaap_NoninterestExpenseDirectorsFees" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noninterest Expense Directors Fees</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoninterestExpenseDirectorsFees" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NoninterestExpenseDirectorsFees"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoninterestExpenseDirectorsFees" xlink:to="lab_us-gaap_NoninterestExpenseDirectorsFees" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear_a485b433-d37d-4af6-988b-670c4decb6c3_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Originated, More than Five Years before Current Fiscal Year</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Originated, More than Five Years before Current Fiscal Year</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear" xlink:to="lab_us-gaap_FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_7a536de3-9a20-4fdb-bfeb-8cb2bcd30e39_terseLabel_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounts, Notes, Loans and Financing Receivable [Line Items]</link:label>
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_label_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts, Notes, Loans and Financing Receivable [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems" xlink:to="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalFundsPurchasedMember_333f2dcb-7b48-4dee-9f27-a72c55b8a308_terseLabel_en-US" xlink:label="lab_us-gaap_FederalFundsPurchasedMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal Funds Purchased [Member]</link:label>
    <link:label id="lab_us-gaap_FederalFundsPurchasedMember_label_en-US" xlink:label="lab_us-gaap_FederalFundsPurchasedMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Funds Purchased [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalFundsPurchasedMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalFundsPurchasedMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalFundsPurchasedMember" xlink:to="lab_us-gaap_FederalFundsPurchasedMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StatementOfFinancialPositionAbstract_3f45cc7f-a2b6-4ec7-acb8-394860cbb3b9_terseLabel_en-US" xlink:label="lab_us-gaap_StatementOfFinancialPositionAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statement of Financial Position [Abstract]</link:label>
    <link:label id="lab_us-gaap_StatementOfFinancialPositionAbstract_label_en-US" xlink:label="lab_us-gaap_StatementOfFinancialPositionAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Financial Position [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfFinancialPositionAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementOfFinancialPositionAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract" xlink:to="lab_us-gaap_StatementOfFinancialPositionAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StockholdersEquity_96b6edad-d1bb-4702-ac38-a5709b25f59e_totalLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total shareholders' equity</link:label>
    <link:label id="lab_us-gaap_StockholdersEquity_9c88a8b2-415c-4a67-b5c8-1497180a1e26_periodStartLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Beginning balances</link:label>
    <link:label id="lab_us-gaap_StockholdersEquity_9df9022d-a297-446f-8b3c-9f82638fac2f_periodEndLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Ending balances</link:label>
    <link:label id="lab_us-gaap_StockholdersEquity_d924300e-0ac0-4cf3-b0b3-94e31c261054_verboseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Shareholders' equity</link:label>
    <link:label id="lab_us-gaap_StockholdersEquity_label_en-US" xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity, Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockholdersEquity"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquity" xlink:to="lab_us-gaap_StockholdersEquity" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_5587dd7e-027e-4107-82a0-aae9b7c6cef5_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Finite-Lived Intangible Assets [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Finite-Lived Intangible Assets [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:to="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RestrictedStockMember_5251d5de-d537-437f-8315-9bd7f3f7cff1_terseLabel_en-US" xlink:label="lab_us-gaap_RestrictedStockMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restricted Stock</link:label>
    <link:label id="lab_us-gaap_RestrictedStockMember_label_en-US" xlink:label="lab_us-gaap_RestrictedStockMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restricted Stock [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RestrictedStockMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestrictedStockMember" xlink:to="lab_us-gaap_RestrictedStockMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis_4d400ecd-1ee3-4a74-877f-ad288d55a603_verboseLabel_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Securities With Variable Monthly Payments or Noncontractual Maturities</link:label>
    <link:label id="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis_label_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities, With Variable Monthly Payments Or Without Single Maturity Date, Amortized Cost Basis</link:label>
    <link:label id="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis_documentation_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities, Debt Maturities, With Variable Monthly Payments Or Without Single Maturity Date, Amortized Cost Basis</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis" xlink:href="isba-20231231.xsd#isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis" xlink:to="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateAmortizedCostBasis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_3d8bfa73-f3dd-4127-b83d-4681a54566a6_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Quantitative information about assets measured utilizing Level 3 fair value measurement</link:label>
    <link:label id="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_label_en-US" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock" xlink:to="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableNonaccrualLoanAndLeaseStatusPolicy_3eff3a3a-06cb-483b-b52e-958abf90c084_terseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableNonaccrualLoanAndLeaseStatusPolicy" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Nonaccrual Loan Status</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableNonaccrualLoanAndLeaseStatusPolicy_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableNonaccrualLoanAndLeaseStatusPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Nonaccrual Loan and Lease Status, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableNonaccrualLoanAndLeaseStatusPolicy" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableNonaccrualLoanAndLeaseStatusPolicy"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableNonaccrualLoanAndLeaseStatusPolicy" xlink:to="lab_us-gaap_LoansAndLeasesReceivableNonaccrualLoanAndLeaseStatusPolicy" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_bbddb52c-33e7-453f-a334-cf47bc9ae09f_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember_45e05eda-3478-46d3-8a25-36c05a06e8dc_terseLabel_en-US" xlink:label="lab_isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Isabella Bank Corporation and Related Companies Deferred Compensation Plan for Directors</link:label>
    <link:label id="lab_isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember_label_en-US" xlink:label="lab_isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Isabella Bank Corporation and Related Companies Deferred Compensation Plan for Directors [Member]</link:label>
    <link:label id="lab_isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember_documentation_en-US" xlink:label="lab_isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Isabella Bank Corporation and Related Companies Deferred Compensation Plan for Directors</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember" xlink:href="isba-20231231.xsd#isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember" xlink:to="lab_isba_IsabellaBankCorporationAndRelatedCompaniesDeferredCompensationPlanForDirectorsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis_548c1d92-6aa6-4675-9d40-27abf5f1dfa8_verboseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maturing, After Ten Years</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Amortized Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ConcentrationRiskByTypeAxis_44406064-c5f4-4ec1-8c92-549b0aac0532_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByTypeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Axis]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskByTypeAxis_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskByTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis" xlink:to="lab_us-gaap_ConcentrationRiskByTypeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableCreditQualityDelinquencyPeriod_48bf756e-b946-4a5a-8a5f-06b0adcd46ac_verboseLabel_en-US" xlink:label="lab_isba_FinancingReceivableCreditQualityDelinquencyPeriod" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Delinquency period</link:label>
    <link:label id="lab_isba_FinancingReceivableCreditQualityDelinquencyPeriod_label_en-US" xlink:label="lab_isba_FinancingReceivableCreditQualityDelinquencyPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Credit Quality, Delinquency Period</link:label>
    <link:label id="lab_isba_FinancingReceivableCreditQualityDelinquencyPeriod_documentation_en-US" xlink:label="lab_isba_FinancingReceivableCreditQualityDelinquencyPeriod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable, Credit Quality, Delinquency Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableCreditQualityDelinquencyPeriod" xlink:href="isba-20231231.xsd#isba_FinancingReceivableCreditQualityDelinquencyPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableCreditQualityDelinquencyPeriod" xlink:to="lab_isba_FinancingReceivableCreditQualityDelinquencyPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubsequentEventsAbstract_3b0bb8e1-843a-40b8-a09c-f52bc3da81a3_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subsequent Events [Abstract]</link:label>
    <link:label id="lab_us-gaap_SubsequentEventsAbstract_label_en-US" xlink:label="lab_us-gaap_SubsequentEventsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Events [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubsequentEventsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsAbstract" xlink:to="lab_us-gaap_SubsequentEventsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract_682dc776-37a7-48be-ab9e-80876fad2cce_verboseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Unrealized gains (losses) on AFS securities</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:to="lab_us-gaap_OtherComprehensiveIncomeAvailableForSaleSecuritiesAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_5cdd6e08-3270-496d-aed9-e8de3bef8df9_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Income before federal income tax expense</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_4ae02113-eda6-4ba6-8c31-b15b161b0651_verboseLabel_en-US" xlink:label="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other Noninterest Expenses</link:label>
    <link:label id="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock_label_en-US" xlink:label="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Income and Other Expense Disclosure [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock" xlink:to="lab_us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock_f3ddb43d-13fa-4b1e-b195-141e8a897b9a_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Measurement</link:label>
    <link:label id="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock_b4106bcf-5bcd-4851-9545-687d29509964_terseLabel_en-US" xlink:label="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Measurement, Policy [Policy Text Block]</link:label>
    <link:label id="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Measurement, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueMeasurementPolicyPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xlink:to="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NondesignatedMember_b0da59a7-3c50-4a17-b60d-2f7f56366814_terseLabel_en-US" xlink:label="lab_us-gaap_NondesignatedMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Not Designated as Hedging Instrument [Member]</link:label>
    <link:label id="lab_us-gaap_NondesignatedMember_label_en-US" xlink:label="lab_us-gaap_NondesignatedMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Not Designated as Hedging Instrument [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NondesignatedMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NondesignatedMember" xlink:to="lab_us-gaap_NondesignatedMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_64d2e91f-c54c-4863-8d1d-10abb49f8e25_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Past Due [Line Items]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Past Due [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems" xlink:to="lab_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue_9244bc7f-c3e8-4290-8ed0-47016ba5ff9c_terseLabel_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities, With Variable Monthly Payments Or Without Single Maturity Date, Fair Value</link:label>
    <link:label id="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue_label_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities, With Variable Monthly Payments Or Without Single Maturity Date, Fair Value</link:label>
    <link:label id="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue_documentation_en-US" xlink:label="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Available-for-sale Securities, With Variable Monthly Payments Or Without Single Maturity Date, Fair Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue" xlink:href="isba-20231231.xsd#isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue" xlink:to="lab_isba_AvailableforsaleSecuritiesWithVariableMonthlyPaymentsOrWithoutSingleMaturityDateFairValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_USStatesAndPoliticalSubdivisionsMember_fae72dd9-86c8-4a8a-8b58-a327891e1285_verboseLabel_en-US" xlink:label="lab_us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">States and political subdivisions [Member]</link:label>
    <link:label id="lab_us-gaap_USStatesAndPoliticalSubdivisionsMember_label_en-US" xlink:label="lab_us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">US States and Political Subdivisions Debt Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:to="lab_us-gaap_USStatesAndPoliticalSubdivisionsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment_ac76e3cc-8616-48b9-814a-75010c3252d1_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Realized Gain (Loss), Excluding Other-than-temporary Impairment</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Realized Gain (Loss), Excluding Other-than-temporary Impairment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLossExcludingOtherThanTemporaryImpairment" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_HedgingDesignationDomain_cd438166-daf3-42e9-8b38-b3d2f039ad0c_terseLabel_en-US" xlink:label="lab_us-gaap_HedgingDesignationDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Hedging Designation [Domain]</link:label>
    <link:label id="lab_us-gaap_HedgingDesignationDomain_label_en-US" xlink:label="lab_us-gaap_HedgingDesignationDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Hedging Designation [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_HedgingDesignationDomain" xlink:to="lab_us-gaap_HedgingDesignationDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueInputsLevel2Member_06751cba-55b5-4666-bac0-a6e1b0968769_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel2Member" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Level 2 [Member]</link:label>
    <link:label id="lab_us-gaap_FairValueInputsLevel2Member_label_en-US" xlink:label="lab_us-gaap_FairValueInputsLevel2Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value, Inputs, Level 2 [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel2Member" xlink:to="lab_us-gaap_FairValueInputsLevel2Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses_59e146c4-67fc-43d5-8c85-f5fae25818f4_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Allowance for loan losses</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Asset, Tax Deferred Expense, Reserve and Accrual, Financing Receivable, Allowance for Credit Loss</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses" xlink:to="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_EquityMethodAndOtherInvestments_8aca56fb-693b-4dbc-926e-6a690d5ca2b0_verboseLabel_en-US" xlink:label="lab_isba_EquityMethodAndOtherInvestments" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Equity securities without readily determinable fair values</link:label>
    <link:label id="lab_isba_EquityMethodAndOtherInvestments_2288e643-4741-4d1c-b7f2-37c55b4aac34_terseLabel_en-US" xlink:label="lab_isba_EquityMethodAndOtherInvestments" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:label id="lab_isba_EquityMethodAndOtherInvestments_label_en-US" xlink:label="lab_isba_EquityMethodAndOtherInvestments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Method And Other Investments</link:label>
    <link:label id="lab_isba_EquityMethodAndOtherInvestments_documentation_en-US" xlink:label="lab_isba_EquityMethodAndOtherInvestments" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Equity Method And Other Investments</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_EquityMethodAndOtherInvestments" xlink:href="isba-20231231.xsd#isba_EquityMethodAndOtherInvestments"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_EquityMethodAndOtherInvestments" xlink:to="lab_isba_EquityMethodAndOtherInvestments" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CondensedIncomeStatementTable_a5553b83-968b-4666-abcf-ea34381420c4_terseLabel_en-US" xlink:label="lab_srt_CondensedIncomeStatementTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Condensed Income Statement [Table]</link:label>
    <link:label id="lab_srt_CondensedIncomeStatementTable_label_en-US" xlink:label="lab_srt_CondensedIncomeStatementTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Income Statement [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedIncomeStatementTable" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CondensedIncomeStatementTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CondensedIncomeStatementTable" xlink:to="lab_srt_CondensedIncomeStatementTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable_2aeae338-4247-4982-9d9d-ee003140aed9_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable" xlink:to="lab_us-gaap_ScheduleOfEarningsPerShareDilutedByCommonClassTable" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount_228c7b38-1257-4e20-8b27-6d39d5b255aa_terseLabel_en-US" xlink:label="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount</link:label>
    <link:label id="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount_label_en-US" xlink:label="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount</link:label>
    <link:label id="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount_documentation_en-US" xlink:label="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Impaired Financing Receivable, Fair Value Disclosure, Appraised Value Discount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount" xlink:href="isba-20231231.xsd#isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount" xlink:to="lab_isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsForProceedsFromInvestmentsAbstract_c701db61-6e9c-4017-b7fd-b7b710d7adc7_verboseLabel_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromInvestmentsAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Activity in AFS securities</link:label>
    <link:label id="lab_us-gaap_PaymentsForProceedsFromInvestmentsAbstract_label_en-US" xlink:label="lab_us-gaap_PaymentsForProceedsFromInvestmentsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments for (Proceeds from) Investments [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForProceedsFromInvestmentsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsForProceedsFromInvestmentsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForProceedsFromInvestmentsAbstract" xlink:to="lab_us-gaap_PaymentsForProceedsFromInvestmentsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_1955f83d-f4fa-4252-9406-079b398a69e2_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Stockholders' Equity [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Stockholders' Equity [Roll Forward]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_SummaryOfOtherNoninterestExpensesAbstract_3bf3ae62-33a8-4972-88ba-314370d43737_verboseLabel_en-US" xlink:label="lab_isba_SummaryOfOtherNoninterestExpensesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of expenses included in other noninterest expenses</link:label>
    <link:label id="lab_isba_SummaryOfOtherNoninterestExpensesAbstract_label_en-US" xlink:label="lab_isba_SummaryOfOtherNoninterestExpensesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Summary of Other Noninterest Expenses [Abstract]</link:label>
    <link:label id="lab_isba_SummaryOfOtherNoninterestExpensesAbstract_documentation_en-US" xlink:label="lab_isba_SummaryOfOtherNoninterestExpensesAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Summary of other noninterest expenses.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_SummaryOfOtherNoninterestExpensesAbstract" xlink:href="isba-20231231.xsd#isba_SummaryOfOtherNoninterestExpensesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_SummaryOfOtherNoninterestExpensesAbstract" xlink:to="lab_isba_SummaryOfOtherNoninterestExpensesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend_dc621d39-e168-45a3-828d-7a8bdd60872a_verboseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Advance in connection with impaired loans</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Modified, Commitment to Lend</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend" xlink:to="lab_us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease_b4860043-6948-40d5-b420-e47298233838_terseLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits</link:label>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease_label_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits, Period Increase (Decrease)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentFiscalPeriodFocus_c298e4b8-773a-41fc-a9a2-a8996a21231f_terseLabel_en-US" xlink:label="lab_dei_DocumentFiscalPeriodFocus" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Fiscal Period Focus</link:label>
    <link:label id="lab_dei_DocumentFiscalPeriodFocus_label_en-US" xlink:label="lab_dei_DocumentFiscalPeriodFocus" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Fiscal Period Focus</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalPeriodFocus" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentFiscalPeriodFocus"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentFiscalPeriodFocus" xlink:to="lab_dei_DocumentFiscalPeriodFocus" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansReceivableMember_9171c2cc-e122-4ad6-896e-30d1e00a8386_terseLabel_en-US" xlink:label="lab_us-gaap_LoansReceivableMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans Receivable</link:label>
    <link:label id="lab_us-gaap_LoansReceivableMember_label_en-US" xlink:label="lab_us-gaap_LoansReceivableMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansReceivableMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansReceivableMember" xlink:to="lab_us-gaap_LoansReceivableMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue_0fb83eef-698f-4e07-9ba6-e1ca949e5f66_verboseLabel_en-US" xlink:label="lab_isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock transferred from the Rabbi Trust to satisfy deferred compensation obligations</link:label>
    <link:label id="lab_isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue_label_en-US" xlink:label="lab_isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Compensation, Shares Transferred From Trust To Common Stock, Value</link:label>
    <link:label id="lab_isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue_documentation_en-US" xlink:label="lab_isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Common stock transferred from the Rabbi Trust to satisfy deferred compensation obligations.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue" xlink:href="isba-20231231.xsd#isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue" xlink:to="lab_isba_ShareBasedCompensationSharesTransferredFromTrustToCommonStockValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShareBasedCompensation_6300abe1-b4ed-4b36-802b-02611f14823b_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Share-based payment awards under equity compensation plan</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensation_0ad434f6-f17f-4f0d-96c3-5e5f6aa89cfe_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based payment awards</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensation_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Payment Arrangement, Noncash Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShareBasedCompensation"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensation" xlink:to="lab_us-gaap_ShareBasedCompensation" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ConsumerSecuredIndirectPortfolioSegmentMember_c41219f2-b4a7-4eff-95f2-df824aaa4c7a_terseLabel_en-US" xlink:label="lab_isba_ConsumerSecuredIndirectPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consumer, Secured, Indirect, Portfolio Segment</link:label>
    <link:label id="lab_isba_ConsumerSecuredIndirectPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_ConsumerSecuredIndirectPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consumer, Secured, Indirect, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_ConsumerSecuredIndirectPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_ConsumerSecuredIndirectPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Consumer, Secured, Indirect, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ConsumerSecuredIndirectPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_ConsumerSecuredIndirectPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ConsumerSecuredIndirectPortfolioSegmentMember" xlink:to="lab_isba_ConsumerSecuredIndirectPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OffBalanceSheetCreditLossLiability_c6587918-a8b4-4104-876f-86303771b90e_terseLabel_en-US" xlink:label="lab_us-gaap_OffBalanceSheetCreditLossLiability" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Off-Balance-Sheet, Credit Loss, Liability</link:label>
    <link:label id="lab_us-gaap_OffBalanceSheetCreditLossLiability_label_en-US" xlink:label="lab_us-gaap_OffBalanceSheetCreditLossLiability" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Off-Balance-Sheet, Credit Loss, Liability</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OffBalanceSheetCreditLossLiability" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OffBalanceSheetCreditLossLiability"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OffBalanceSheetCreditLossLiability" xlink:to="lab_us-gaap_OffBalanceSheetCreditLossLiability" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_CityAreaCode_1f54aa42-63a6-4982-b9cb-8d48eeb197a9_terseLabel_en-US" xlink:label="lab_dei_CityAreaCode" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">City Area Code</link:label>
    <link:label id="lab_dei_CityAreaCode_label_en-US" xlink:label="lab_dei_CityAreaCode" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">City Area Code</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_CityAreaCode"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_CityAreaCode" xlink:to="lab_dei_CityAreaCode" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_ProductOrServiceAxis_c1112691-561b-4557-bee5-0c9066264c85_terseLabel_en-US" xlink:label="lab_srt_ProductOrServiceAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Product and Service [Axis]</link:label>
    <link:label id="lab_srt_ProductOrServiceAxis_label_en-US" xlink:label="lab_srt_ProductOrServiceAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product and Service [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_ProductOrServiceAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ProductOrServiceAxis" xlink:to="lab_srt_ProductOrServiceAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivablesPeriodPastDueDomain_fdd5eb58-e1aa-4383-85a0-56e9e22c1f6f_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Assets, Period Past Due [Domain]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivablesPeriodPastDueDomain_label_en-US" xlink:label="lab_us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Asset, Aging [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:to="lab_us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_EarningsPerShareTextBlock_67fc9665-d663-49c1-9046-c88997a3e0d0_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Computation of Earnings Per Common Share</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareTextBlock_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share [Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_EarningsPerShareTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareTextBlock" xlink:to="lab_us-gaap_EarningsPerShareTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_CondensedIncomeStatementsCaptionsLineItems_06a8333e-cf43-4816-b782-e9e372c6790b_terseLabel_en-US" xlink:label="lab_srt_CondensedIncomeStatementsCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Condensed Income Statements, Captions [Line Items]</link:label>
    <link:label id="lab_srt_CondensedIncomeStatementsCaptionsLineItems_label_en-US" xlink:label="lab_srt_CondensedIncomeStatementsCaptionsLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Condensed Income Statements, Captions [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CondensedIncomeStatementsCaptionsLineItems" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_CondensedIncomeStatementsCaptionsLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems" xlink:to="lab_srt_CondensedIncomeStatementsCaptionsLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesLongTerm_7e34eaf3-436d-4e93-8f6b-253437de7961_terseLabel_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesLongTerm" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term Federal Home Loan Bank Advances</link:label>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesLongTerm_label_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesLongTerm" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-Term Federal Home Loan Bank Advances</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankAdvancesLongTerm" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalHomeLoanBankAdvancesLongTerm"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalHomeLoanBankAdvancesLongTerm" xlink:to="lab_us-gaap_FederalHomeLoanBankAdvancesLongTerm" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommitmentsToExtendCreditMember_6f8c4e1c-42f5-40a1-8d0e-8bb074810027_terseLabel_en-US" xlink:label="lab_us-gaap_CommitmentsToExtendCreditMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commitments to Extend Credit</link:label>
    <link:label id="lab_us-gaap_CommitmentsToExtendCreditMember_label_en-US" xlink:label="lab_us-gaap_CommitmentsToExtendCreditMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments to Extend Credit [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsToExtendCreditMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommitmentsToExtendCreditMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsToExtendCreditMember" xlink:to="lab_us-gaap_CommitmentsToExtendCreditMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PerformanceBonusExpense_a16b0d93-1ed6-47ca-af0e-5b5a7d0a9b56_terseLabel_en-US" xlink:label="lab_isba_PerformanceBonusExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Performance bonus expense</link:label>
    <link:label id="lab_isba_PerformanceBonusExpense_label_en-US" xlink:label="lab_isba_PerformanceBonusExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Performance Bonus Expense</link:label>
    <link:label id="lab_isba_PerformanceBonusExpense_documentation_en-US" xlink:label="lab_isba_PerformanceBonusExpense" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Performance Bonus Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PerformanceBonusExpense" xlink:href="isba-20231231.xsd#isba_PerformanceBonusExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PerformanceBonusExpense" xlink:to="lab_isba_PerformanceBonusExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherNoninterestExpense_557c2afd-9f08-4204-b06d-7c2bb8397cc5_verboseLabel_en-US" xlink:label="lab_us-gaap_OtherNoninterestExpense" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_OtherNoninterestExpense_7dd1aee7-9188-43eb-897e-70a51d5e125c_totalLabel_en-US" xlink:label="lab_us-gaap_OtherNoninterestExpense" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total other</link:label>
    <link:label id="lab_us-gaap_OtherNoninterestExpense_label_en-US" xlink:label="lab_us-gaap_OtherNoninterestExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Noninterest Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoninterestExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherNoninterestExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherNoninterestExpense" xlink:to="lab_us-gaap_OtherNoninterestExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_DocumentFiscalYearFocus_916220d6-1c48-48ff-bd6b-9de9cb6d57c4_terseLabel_en-US" xlink:label="lab_dei_DocumentFiscalYearFocus" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document Fiscal Year Focus</link:label>
    <link:label id="lab_dei_DocumentFiscalYearFocus_label_en-US" xlink:label="lab_dei_DocumentFiscalYearFocus" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Fiscal Year Focus</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalYearFocus" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_DocumentFiscalYearFocus"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentFiscalYearFocus" xlink:to="lab_dei_DocumentFiscalYearFocus" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Deposits_1f2fc945-cebb-495c-aaba-708a1702e31b_totalLabel_en-US" xlink:label="lab_us-gaap_Deposits" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total deposits</link:label>
    <link:label id="lab_us-gaap_Deposits_label_en-US" xlink:label="lab_us-gaap_Deposits" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deposits</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Deposits" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Deposits"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Deposits" xlink:to="lab_us-gaap_Deposits" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue_bd0710b3-0cac-4e19-8b7e-1a4dac849e8c_totalLabel_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Market value, total</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue_label_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Common Stock Issued and Reserved for Future Issuance, Value</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue_documentation_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Common Stock Issued and Reserved for Future Issuance, Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue" xlink:href="isba-20231231.xsd#isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue" xlink:to="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceValue" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow_86d72ed3-9f14-4a28-b9d3-362f838be51f_verboseLabel_en-US" xlink:label="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Pledged to secure borrowed funds</link:label>
    <link:label id="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow_label_en-US" xlink:label="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Pledged Financial Instruments, Not Separately Reported, Securities And Loans Receivable, For Federal Home Loan Bank Debt And Federal Reserve Bank Discount Window</link:label>
    <link:label id="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow_documentation_en-US" xlink:label="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Pledged Financial Instruments, Not Separately Reported, Securities And Loans Receivable, For Federal Home Loan Bank Debt And Federal Reserve Bank Discount Window</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow" xlink:href="isba-20231231.xsd#isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow" xlink:to="lab_isba_PledgedFinancialInstrumentsNotSeparatelyReportedSecuritiesAndLoansReceivableForFederalHomeLoanBankDebtAndFederalReserveBankDiscountWindow" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock_191e75b6-908c-405a-9931-360a2e1009f3_verboseLabel_en-US" xlink:label="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">EQUITY COMPENSATION PLAN</link:label>
    <link:label id="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Compensation Related Costs, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CompensationRelatedCostsPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CompensationRelatedCostsPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CompensationRelatedCostsPolicyTextBlock" xlink:to="lab_us-gaap_CompensationRelatedCostsPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance_3e18da66-c40f-4c9d-bbcb-e8a5d4178fbd_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Eligible shares, unissued</link:label>
    <link:label id="lab_us-gaap_DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance_label_en-US" xlink:label="lab_us-gaap_DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Common Stock Reserved for Future Issuance</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance" xlink:to="lab_us-gaap_DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue_0f7b1323-1660-4214-9d5f-90683ee22b87_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after Five Through Ten Years, Fair Value</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 5 through 10 Years, Fair Value</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReceivablesAbstract_418f12f5-07fe-4bfc-85d0-948a21773625_terseLabel_en-US" xlink:label="lab_us-gaap_ReceivablesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Receivables [Abstract]</link:label>
    <link:label id="lab_us-gaap_ReceivablesAbstract_label_en-US" xlink:label="lab_us-gaap_ReceivablesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Receivables [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivablesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ReceivablesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReceivablesAbstract" xlink:to="lab_us-gaap_ReceivablesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_dbb5f33b-379c-486a-abea-8f7b7fcbe6cf_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalReserveBankStock_9687c90d-77d2-40e5-83fe-9300ef8be8d7_terseLabel_en-US" xlink:label="lab_us-gaap_FederalReserveBankStock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">FRB Stock</link:label>
    <link:label id="lab_us-gaap_FederalReserveBankStock_label_en-US" xlink:label="lab_us-gaap_FederalReserveBankStock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Reserve Bank Stock</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalReserveBankStock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalReserveBankStock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalReserveBankStock" xlink:to="lab_us-gaap_FederalReserveBankStock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneLeverageCapital_513e1b4f-82b8-4fdc-9526-c27946f5f38a_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapital" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Actual Amount</link:label>
    <link:label id="lab_us-gaap_TierOneLeverageCapital_label_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapital" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Leverage Capital, Actual</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapital" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneLeverageCapital"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneLeverageCapital" xlink:to="lab_us-gaap_TierOneLeverageCapital" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DividendsCommonStockCash_fcaed0ac-5d79-4d53-9b8c-2e9627bd99df_negatedLabel_en-US" xlink:label="lab_us-gaap_DividendsCommonStockCash" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Cash dividends</link:label>
    <link:label id="lab_us-gaap_DividendsCommonStockCash_label_en-US" xlink:label="lab_us-gaap_DividendsCommonStockCash" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Dividends, Common Stock, Cash</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStockCash" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DividendsCommonStockCash"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DividendsCommonStockCash" xlink:to="lab_us-gaap_DividendsCommonStockCash" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_34f8832a-8fae-4653-b44b-214cf5d2c7c0_terseLabel_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Goodwill and Intangible Assets Disclosure [Abstract]</link:label>
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract_label_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill and Intangible Assets Disclosure [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:to="lab_us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember_5bf261fa-ba99-4162-b913-143c103e7b37_terseLabel_en-US" xlink:label="lab_isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Residential Real Estate, Junior Lien, Portfolio Segment</link:label>
    <link:label id="lab_isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Residential Real Estate, Junior Lien, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Residential Real Estate, Junior Lien, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember" xlink:to="lab_isba_ResidentialRealEstateJuniorLienPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_SafeHarbor401kMember_d5bf3937-2441-401b-b092-0fbae7ae94c1_terseLabel_en-US" xlink:label="lab_isba_SafeHarbor401kMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Safe Harbor 401(k) [Member]</link:label>
    <link:label id="lab_isba_SafeHarbor401kMember_label_en-US" xlink:label="lab_isba_SafeHarbor401kMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Safe Harbor 401(k) [Member]</link:label>
    <link:label id="lab_isba_SafeHarbor401kMember_documentation_en-US" xlink:label="lab_isba_SafeHarbor401kMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Safe Harbor 401(k) [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_SafeHarbor401kMember" xlink:href="isba-20231231.xsd#isba_SafeHarbor401kMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_SafeHarbor401kMember" xlink:to="lab_isba_SafeHarbor401kMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod_6f50b884-d74e-4244-8279-82a676ea2743_terseLabel_en-US" xlink:label="lab_isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Threshold period of continuous performance to return loans to accrual status</link:label>
    <link:label id="lab_isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod_label_en-US" xlink:label="lab_isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Continuing Performance, Accrual Of Interest, Threshold Period</link:label>
    <link:label id="lab_isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod_documentation_en-US" xlink:label="lab_isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable, Continuing Performance, Accrual Of Interest, Threshold Period</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod" xlink:href="isba-20231231.xsd#isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod" xlink:to="lab_isba_FinancingReceivableContinuingPerformanceAccrualOfInterestThresholdPeriod" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions_6584a168-fc86-4dbd-b9a3-3a36b4682a7f_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OccupancyNet_c7e5f4f2-669c-4489-bd63-8fecce887d4e_verboseLabel_en-US" xlink:label="lab_us-gaap_OccupancyNet" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Occupancy</link:label>
    <link:label id="lab_us-gaap_OccupancyNet_label_en-US" xlink:label="lab_us-gaap_OccupancyNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Occupancy, Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OccupancyNet" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OccupancyNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OccupancyNet" xlink:to="lab_us-gaap_OccupancyNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquity_e7b95a57-7108-4904-8c73-bbec640858f3_totalLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Liabilities and Equity, Total</link:label>
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquity_1d5b06aa-a244-44dd-ad29-687ee185f956_terseLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Liabilities and Equity, Total</link:label>
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquity_label_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities and Equity</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="lab_us-gaap_LiabilitiesAndStockholdersEquity" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_3868b92e-2df1-4420-8942-c7665a242b77_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Amortized Cost</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Amortized Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:to="lab_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CashAndDueFromBanks_7e216838-33f5-4b8e-b72a-a3fdccdf6807_verboseLabel_en-US" xlink:label="lab_us-gaap_CashAndDueFromBanks" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cash and demand deposits due from banks</link:label>
    <link:label id="lab_us-gaap_CashAndDueFromBanks_label_en-US" xlink:label="lab_us-gaap_CashAndDueFromBanks" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Due from Banks</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndDueFromBanks" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndDueFromBanks"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndDueFromBanks" xlink:to="lab_us-gaap_CashAndDueFromBanks" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer_4924501f-e515-44b9-bae0-5b0f8bef5d82_terseLabel_en-US" xlink:label="lab_isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer_label_en-US" xlink:label="lab_isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:label id="lab_isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer_documentation_en-US" xlink:label="lab_isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:href="isba-20231231.xsd#isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:to="lab_isba_CapitalRequiredForCapitalAdequacyMinimumCapitalRequiredPlusCapitalConservationBuffer" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_NoninterestIncomeServiceChargesandFees_0349496a-0aa1-4daa-82c6-0e99e91cf829_verboseLabel_en-US" xlink:label="lab_isba_NoninterestIncomeServiceChargesandFees" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Service charges and fees</link:label>
    <link:label id="lab_isba_NoninterestIncomeServiceChargesandFees_label_en-US" xlink:label="lab_isba_NoninterestIncomeServiceChargesandFees" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noninterest Income, Service Charges and Fees</link:label>
    <link:label id="lab_isba_NoninterestIncomeServiceChargesandFees_documentation_en-US" xlink:label="lab_isba_NoninterestIncomeServiceChargesandFees" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Noninterest Income, Service Charges and Fees</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_NoninterestIncomeServiceChargesandFees" xlink:href="isba-20231231.xsd#isba_NoninterestIncomeServiceChargesandFees"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_NoninterestIncomeServiceChargesandFees" xlink:to="lab_isba_NoninterestIncomeServiceChargesandFees" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CollateralPledgedMember_0bbfd11f-6447-4d07-8ad8-a25e87ba51a6_terseLabel_en-US" xlink:label="lab_us-gaap_CollateralPledgedMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Collateral Pledged</link:label>
    <link:label id="lab_us-gaap_CollateralPledgedMember_label_en-US" xlink:label="lab_us-gaap_CollateralPledgedMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Collateral Pledged [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralPledgedMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CollateralPledgedMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CollateralPledgedMember" xlink:to="lab_us-gaap_CollateralPledgedMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_f89227b3-7963-494a-b950-5f71811c79b9_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityAddressCityOrTown_d87376b9-5527-46a6-a2f4-ed596559dbc1_terseLabel_en-US" xlink:label="lab_dei_EntityAddressCityOrTown" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Address, City or Town</link:label>
    <link:label id="lab_dei_EntityAddressCityOrTown_label_en-US" xlink:label="lab_dei_EntityAddressCityOrTown" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Address, City or Town</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityAddressCityOrTown"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressCityOrTown" xlink:to="lab_dei_EntityAddressCityOrTown" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DocumentAndEntityInformationAbstract_2d89247e-6709-481c-8161-06166d3f4bae_terseLabel_en-US" xlink:label="lab_isba_DocumentAndEntityInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Document and Entity Information [Abstract]</link:label>
    <link:label id="lab_isba_DocumentAndEntityInformationAbstract_label_en-US" xlink:label="lab_isba_DocumentAndEntityInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document and Entity Information [Abstract]</link:label>
    <link:label id="lab_isba_DocumentAndEntityInformationAbstract_documentation_en-US" xlink:label="lab_isba_DocumentAndEntityInformationAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Document and entity information.</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DocumentAndEntityInformationAbstract" xlink:href="isba-20231231.xsd#isba_DocumentAndEntityInformationAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DocumentAndEntityInformationAbstract" xlink:to="lab_isba_DocumentAndEntityInformationAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TimeDepositsByMaturityAbstract_012fbd47-017f-42f8-ae6f-f0058a969879_verboseLabel_en-US" xlink:label="lab_us-gaap_TimeDepositsByMaturityAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Scheduled maturities of time deposits</link:label>
    <link:label id="lab_us-gaap_TimeDepositsByMaturityAbstract_label_en-US" xlink:label="lab_us-gaap_TimeDepositsByMaturityAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Time Deposits, Fiscal Year Maturity [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsByMaturityAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TimeDepositsByMaturityAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimeDepositsByMaturityAbstract" xlink:to="lab_us-gaap_TimeDepositsByMaturityAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeTaxReconciliationTaxCredits_b4b2f9cc-2d23-43b5-954c-c0aaa6707415_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxReconciliationTaxCredits" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Effect of tax credits</link:label>
    <link:label id="lab_us-gaap_IncomeTaxReconciliationTaxCredits_label_en-US" xlink:label="lab_us-gaap_IncomeTaxReconciliationTaxCredits" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Credit, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReconciliationTaxCredits" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxReconciliationTaxCredits"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReconciliationTaxCredits" xlink:to="lab_us-gaap_IncomeTaxReconciliationTaxCredits" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LoansReceivableCollateralizedByCashCropInventoryMember_fbc9ddfe-866d-4b02-8daf-08d76d73870e_terseLabel_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByCashCropInventoryMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Cash Crop Inventory [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByCashCropInventoryMember_label_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByCashCropInventoryMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Cash Crop Inventory [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByCashCropInventoryMember_documentation_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByCashCropInventoryMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Cash Crop Inventory [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LoansReceivableCollateralizedByCashCropInventoryMember" xlink:href="isba-20231231.xsd#isba_LoansReceivableCollateralizedByCashCropInventoryMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LoansReceivableCollateralizedByCashCropInventoryMember" xlink:to="lab_isba_LoansReceivableCollateralizedByCashCropInventoryMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFinancialInstrumentsOwnedAndPledgedAsCollateralTextBlock_9a139c99-03c0-49cc-a730-f6b6889a8ce4_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancialInstrumentsOwnedAndPledgedAsCollateralTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of pledged financial instruments</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFinancialInstrumentsOwnedAndPledgedAsCollateralTextBlock_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancialInstrumentsOwnedAndPledgedAsCollateralTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Financial Instruments Owned and Pledged as Collateral [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancialInstrumentsOwnedAndPledgedAsCollateralTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFinancialInstrumentsOwnedAndPledgedAsCollateralTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFinancialInstrumentsOwnedAndPledgedAsCollateralTextBlock" xlink:to="lab_us-gaap_ScheduleOfFinancialInstrumentsOwnedAndPledgedAsCollateralTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations_0adcbd51-dab3-4d2a-b201-361b950d75e8_verboseLabel_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Shares to be issued for deferred compensation obligations</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations_label_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Deferred Compensation Obligations</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations_documentation_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Deferred Compensation Obligations</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations" xlink:href="isba-20231231.xsd#isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations" xlink:to="lab_isba_DeferredCompensationArrangementwithIndividualDeferredCompensationObligations" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInDeposits_100f9da3-8641-42a3-a3d3-6de0ab2c49d9_verboseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInDeposits" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net increase (decrease) in deposits</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInDeposits_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInDeposits" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Deposits</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInDeposits" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncreaseDecreaseInDeposits"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInDeposits" xlink:to="lab_us-gaap_IncreaseDecreaseInDeposits" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CommonStockSharesAuthorized_35742f7b-a728-4f3d-838d-a98bf05d67cb_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares authorized</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesAuthorized_label_en-US" xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares Authorized</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesAuthorized" xlink:to="lab_us-gaap_CommonStockSharesAuthorized" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_8da34527-6989-43ef-82e1-ea6c9c7df5b9_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivablesPastDueTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivables Past Due [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivablesPastDueTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Past Due [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfFinancingReceivablesPastDueTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable" xlink:to="lab_us-gaap_ScheduleOfFinancingReceivablesPastDueTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase_83fe8f23-5307-4b4e-b43f-d2daf8dd1a0c_terseLabel_en-US" xlink:label="lab_us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal Funds Purchased and Securities Sold under Agreements to Repurchase</link:label>
    <link:label id="lab_us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase_label_en-US" xlink:label="lab_us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Funds Purchased and Securities Sold under Agreements to Repurchase</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:to="lab_us-gaap_FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities_644bc09b-f5ad-4830-bfe6-9481becc1157_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:to="lab_us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CapitalRequiredToBeWellCapitalized_a77c4748-aeec-4b6a-8e6c-4167cb1b92d7_verboseLabel_en-US" xlink:label="lab_us-gaap_CapitalRequiredToBeWellCapitalized" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions Amount</link:label>
    <link:label id="lab_us-gaap_CapitalRequiredToBeWellCapitalized_label_en-US" xlink:label="lab_us-gaap_CapitalRequiredToBeWellCapitalized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Total Risk-Based Capital, Well Capitalized, Minimum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalRequiredToBeWellCapitalized" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CapitalRequiredToBeWellCapitalized"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalRequiredToBeWellCapitalized" xlink:to="lab_us-gaap_CapitalRequiredToBeWellCapitalized" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivablesPeriodPastDueAxis_7f2e1e7e-dba3-42a6-a773-3b052e9e1cd1_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financial Assets, Period Past Due [Axis]</link:label>
    <link:label id="lab_us-gaap_FinancingReceivablesPeriodPastDueAxis_label_en-US" xlink:label="lab_us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Asset, Aging [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:to="lab_us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_d6c15d9c-6597-4149-affa-3031e41ac255_terseLabel_en-US" xlink:label="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax</link:label>
    <link:label id="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_label_en-US" xlink:label="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:to="lab_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount_59340068-259b-42a7-ac23-e6b5feecce65_verboseLabel_en-US" xlink:label="lab_us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum Month End Balance</link:label>
    <link:label id="lab_us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount_label_en-US" xlink:label="lab_us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Debt, Maximum Month-end Outstanding Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount" xlink:to="lab_us-gaap_ShorttermDebtMaximumMonthendOutstandingAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock_e1b7a1c9-7061-41a7-a0a1-8207866dca01_terseLabel_en-US" xlink:label="lab_isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Effects of Loan Modifications for Borrowers Experiencing Financial Difficulty</link:label>
    <link:label id="lab_isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock_label_en-US" xlink:label="lab_isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Financial Effects of Loans Held for Investment Modified for Borrowers Experiencing Financial Difficulty [Table Text Block]</link:label>
    <link:label id="lab_isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock_documentation_en-US" xlink:label="lab_isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of Financial Effects of Loans Held for Investment Modified for Borrowers Experiencing Financial Difficulty</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock" xlink:href="isba-20231231.xsd#isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock" xlink:to="lab_isba_ScheduleOfFinancialEffectsOfLoansHeldForInvestmentModifiedForBorrowersExperiencingFinancialDifficultyTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_4fa4f453-910c-4f5c-a060-21807fff5134_verboseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Reconciliation of net income to net cash provided by operating activities:</link:label>
    <link:label id="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_d8e34a03-a375-473e-8d69-94e99fc53359_terseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Adjustments to reconcile net income to cash provided by operations</link:label>
    <link:label id="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_label_en-US" xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RelatedPartyTransactionsAbstract_dc09dd99-f34e-449c-86ff-54cd4ab295fd_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party Transactions [Abstract]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionsAbstract_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transactions [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionsAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsAbstract" xlink:to="lab_us-gaap_RelatedPartyTransactionsAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LoansReceivableCollateralizedByAccountsReceivableMember_94efc0ec-906a-47d7-81c0-771b924eb4a3_terseLabel_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByAccountsReceivableMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Accounts Receivable [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByAccountsReceivableMember_label_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByAccountsReceivableMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Accounts Receivable [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByAccountsReceivableMember_documentation_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByAccountsReceivableMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Accounts Receivable [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LoansReceivableCollateralizedByAccountsReceivableMember" xlink:href="isba-20231231.xsd#isba_LoansReceivableCollateralizedByAccountsReceivableMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LoansReceivableCollateralizedByAccountsReceivableMember" xlink:to="lab_isba_LoansReceivableCollateralizedByAccountsReceivableMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DerivativeLineItems_84f5f0c0-187d-413a-8d5b-e9f5845e771f_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative [Line Items]</link:label>
    <link:label id="lab_us-gaap_DerivativeLineItems_label_en-US" xlink:label="lab_us-gaap_DerivativeLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DerivativeLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeLineItems" xlink:to="lab_us-gaap_DerivativeLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneLeverageCapitalToAverageAssets_ab29f526-3f8c-42ce-a849-d60b51b1afa9_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapitalToAverageAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Actual Ratio</link:label>
    <link:label id="lab_us-gaap_TierOneLeverageCapitalToAverageAssets_label_en-US" xlink:label="lab_us-gaap_TierOneLeverageCapitalToAverageAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Leverage Capital Ratio, Actual</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneLeverageCapitalToAverageAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneLeverageCapitalToAverageAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneLeverageCapitalToAverageAssets" xlink:to="lab_us-gaap_TierOneLeverageCapitalToAverageAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_srt_TitleOfIndividualWithRelationshipToEntityDomain_0dc7b34f-9006-4f96-aaaf-f6f3ab0a56f8_terseLabel_en-US" xlink:label="lab_srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Title of Individual with Relationship to Entity [Domain]</link:label>
    <link:label id="lab_srt_TitleOfIndividualWithRelationshipToEntityDomain_label_en-US" xlink:label="lab_srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Title of Individual [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:href="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:to="lab_srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits_4e3d8b3a-a133-487c-81ce-54208b220cf5_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Employee benefit plans</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xlink:to="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_e4985754-3802-4605-8130-279929662359_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Accounts, Notes, Loans and Financing Receivable [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Accounts, Notes, Loans and Financing Receivable [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable" xlink:to="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit_0d456ff4-93f9-48f1-9c22-b6bde266ec99_terseLabel_en-US" xlink:label="lab_us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Time Deposits, at or Above FDIC Insurance Limit</link:label>
    <link:label id="lab_us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit_label_en-US" xlink:label="lab_us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Time Deposits, at or Above FDIC Insurance Limit</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit" xlink:to="lab_us-gaap_TimeDepositsAtOrAboveFDICInsuranceLimit" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShorttermDebtAverageOutstandingAmount_32ddc408-8ac9-45a4-b23c-3314994e4204_verboseLabel_en-US" xlink:label="lab_us-gaap_ShorttermDebtAverageOutstandingAmount" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Quarter to Date Average Balance</link:label>
    <link:label id="lab_us-gaap_ShorttermDebtAverageOutstandingAmount_label_en-US" xlink:label="lab_us-gaap_ShorttermDebtAverageOutstandingAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Debt, Average Outstanding Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShorttermDebtAverageOutstandingAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShorttermDebtAverageOutstandingAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShorttermDebtAverageOutstandingAmount" xlink:to="lab_us-gaap_ShorttermDebtAverageOutstandingAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DeferredTaxAssetsCompanyOwnedLifeInsurance_ef3c4c49-a670-48fa-96fa-1d0128ad2b12_verboseLabel_en-US" xlink:label="lab_isba_DeferredTaxAssetsCompanyOwnedLifeInsurance" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Life insurance death benefit payable</link:label>
    <link:label id="lab_isba_DeferredTaxAssetsCompanyOwnedLifeInsurance_label_en-US" xlink:label="lab_isba_DeferredTaxAssetsCompanyOwnedLifeInsurance" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Company Owned Life Insurance</link:label>
    <link:label id="lab_isba_DeferredTaxAssetsCompanyOwnedLifeInsurance_documentation_en-US" xlink:label="lab_isba_DeferredTaxAssetsCompanyOwnedLifeInsurance" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Company Owned Life Insurance</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DeferredTaxAssetsCompanyOwnedLifeInsurance" xlink:href="isba-20231231.xsd#isba_DeferredTaxAssetsCompanyOwnedLifeInsurance"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DeferredTaxAssetsCompanyOwnedLifeInsurance" xlink:to="lab_isba_DeferredTaxAssetsCompanyOwnedLifeInsurance" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember_9fcbf3a7-3bce-4b60-8526-a77929e89d7b_terseLabel_en-US" xlink:label="lab_isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Commercial, Agricultural, and Residential Portfolio Segments [Member]</link:label>
    <link:label id="lab_isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember_label_en-US" xlink:label="lab_isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commercial, Agricultural, and Residential Portfolio Segments [Member]</link:label>
    <link:label id="lab_isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember_documentation_en-US" xlink:label="lab_isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Commercial, Agricultural, and Residential Portfolio Segments [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember" xlink:href="isba-20231231.xsd#isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember" xlink:to="lab_isba_CommercialAgriculturalandResidentialPortfolioSegmentsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansReceivableFairValueDisclosure_6a8076d1-10a5-4814-9cdc-631e1130ac32_totalLabel_en-US" xlink:label="lab_us-gaap_LoansReceivableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net loans</link:label>
    <link:label id="lab_us-gaap_LoansReceivableFairValueDisclosure_label_en-US" xlink:label="lab_us-gaap_LoansReceivableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableFairValueDisclosure" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansReceivableFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansReceivableFairValueDisclosure" xlink:to="lab_us-gaap_LoansReceivableFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount_de074409-6d76-460a-9f34-226f61fc24b2_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument, Unused Borrowing Capacity, Amount</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Unused Borrowing Capacity, Amount</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount" xlink:to="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityAmount" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DoubtfulMember_3aa79e48-582c-497e-8762-a85f384853f6_terseLabel_en-US" xlink:label="lab_us-gaap_DoubtfulMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Doubtful [Member]</link:label>
    <link:label id="lab_us-gaap_DoubtfulMember_label_en-US" xlink:label="lab_us-gaap_DoubtfulMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Doubtful [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DoubtfulMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DoubtfulMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DoubtfulMember" xlink:to="lab_us-gaap_DoubtfulMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ShortTermDebtTypeAxis_3858fb4f-0142-48b9-9b63-7b0156b29189_terseLabel_en-US" xlink:label="lab_us-gaap_ShortTermDebtTypeAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Short-term Debt, Type [Axis]</link:label>
    <link:label id="lab_us-gaap_ShortTermDebtTypeAxis_label_en-US" xlink:label="lab_us-gaap_ShortTermDebtTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Short-Term Debt, Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermDebtTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ShortTermDebtTypeAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShortTermDebtTypeAxis" xlink:to="lab_us-gaap_ShortTermDebtTypeAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncomeTaxPolicyTextBlock_83631976-c42b-431e-aa31-fb77e03f4dbb_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">FEDERAL INCOME TAXES</link:label>
    <link:label id="lab_us-gaap_IncomeTaxPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_IncomeTaxPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncomeTaxPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxPolicyTextBlock" xlink:to="lab_us-gaap_IncomeTaxPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NotesReceivableGross_5e564e8c-f320-4817-8ade-297e3389a643_terseLabel_en-US" xlink:label="lab_us-gaap_NotesReceivableGross" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:label id="lab_us-gaap_NotesReceivableGross_label_en-US" xlink:label="lab_us-gaap_NotesReceivableGross" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, before Allowance for Credit Loss</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NotesReceivableGross" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NotesReceivableGross"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NotesReceivableGross" xlink:to="lab_us-gaap_NotesReceivableGross" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoanRestructuringModificationAxis_3e1ddf71-36af-421a-9dd5-933716399cd8_terseLabel_en-US" xlink:label="lab_us-gaap_LoanRestructuringModificationAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loan Restructuring Modification [Axis]</link:label>
    <link:label id="lab_us-gaap_LoanRestructuringModificationAxis_label_en-US" xlink:label="lab_us-gaap_LoanRestructuringModificationAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loan Restructuring Modification [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoanRestructuringModificationAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoanRestructuringModificationAxis" xlink:to="lab_us-gaap_LoanRestructuringModificationAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember_ebd255bd-f467-4fc1-8c90-26f9754c6039_terseLabel_en-US" xlink:label="lab_isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Residential Real Estate, Senior Lien, Portfolio Segment</link:label>
    <link:label id="lab_isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Residential Real Estate, Senior Lien, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Residential Real Estate, Senior Lien, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember" xlink:to="lab_isba_ResidentialRealEstateSeniorLienPortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_203dd1f5-adcf-46dc-aabc-44eb2a8d8551_terseLabel_en-US" xlink:label="lab_us-gaap_AOCIAttributableToParentNetOfTaxRollForward" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_label_en-US" xlink:label="lab_us-gaap_AOCIAttributableToParentNetOfTaxRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">AOCI Attributable to Parent, Net of Tax [Roll Forward]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AOCIAttributableToParentNetOfTaxRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward" xlink:to="lab_us-gaap_AOCIAttributableToParentNetOfTaxRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract_49a99504-1c17-4ee8-a35d-0aad849e417c_verboseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cash and cash equivalents</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, at Carrying Value [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract" xlink:to="lab_us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_7060c806-1c64-454a-8755-52e4ec0a39d6_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party [Axis]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party, Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesRollForward_2919811e-2dc1-4ecc-8c31-51c5b832c1cc_verboseLabel_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesRollForward" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Annual activity</link:label>
    <link:label id="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesRollForward_label_en-US" xlink:label="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans and Leases Receivable, Related Parties [Roll Forward]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansAndLeasesReceivableRelatedPartiesRollForward" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoansAndLeasesReceivableRelatedPartiesRollForward"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansAndLeasesReceivableRelatedPartiesRollForward" xlink:to="lab_us-gaap_LoansAndLeasesReceivableRelatedPartiesRollForward" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestBearingDepositsInBanks_a35a7e9f-09e1-4c3f-96aa-46bd8e976229_verboseLabel_en-US" xlink:label="lab_us-gaap_InterestBearingDepositsInBanks" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interest bearing balances due from banks</link:label>
    <link:label id="lab_us-gaap_InterestBearingDepositsInBanks_label_en-US" xlink:label="lab_us-gaap_InterestBearingDepositsInBanks" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest-Bearing Deposits in Banks and Other Financial Institutions</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestBearingDepositsInBanks" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestBearingDepositsInBanks"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestBearingDepositsInBanks" xlink:to="lab_us-gaap_InterestBearingDepositsInBanks" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityRegistrantName_c00d36b7-a473-4255-85a2-17f5e65d8f64_terseLabel_en-US" xlink:label="lab_dei_EntityRegistrantName" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Registrant Name</link:label>
    <link:label id="lab_dei_EntityRegistrantName_label_en-US" xlink:label="lab_dei_EntityRegistrantName" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Registrant Name</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityRegistrantName"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityRegistrantName" xlink:to="lab_dei_EntityRegistrantName" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherOperatingAssets_5d1270bd-7d87-4dd7-8fe4-b43e14f24101_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Other assets</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherOperatingAssets_8bf9aadd-1546-4d09-bf90-fa977c5f785a_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Other Operating Assets</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherOperatingAssets_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Other Operating Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:to="lab_us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_1466954f-f8fd-45c5-bbb8-e1511b3b5f0b_verboseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year 2</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Asset, Expected Amortization, Year Two</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_AgriculturalMortgagePortfolioSegmentMember_b18ce0e2-6d02-4ba7-b700-24dbcc63a8ac_terseLabel_en-US" xlink:label="lab_isba_AgriculturalMortgagePortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Agricultural Mortgage, Portfolio Segment</link:label>
    <link:label id="lab_isba_AgriculturalMortgagePortfolioSegmentMember_label_en-US" xlink:label="lab_isba_AgriculturalMortgagePortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Agricultural Mortgage, Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_AgriculturalMortgagePortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_AgriculturalMortgagePortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Agricultural Mortgage, Portfolio Segment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_AgriculturalMortgagePortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_AgriculturalMortgagePortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_AgriculturalMortgagePortfolioSegmentMember" xlink:to="lab_isba_AgriculturalMortgagePortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_AuditorName_36ac29dc-759d-47c0-9d70-a0db890bf1e1_terseLabel_en-US" xlink:label="lab_dei_AuditorName" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Auditor Name</link:label>
    <link:label id="lab_dei_AuditorName_label_en-US" xlink:label="lab_dei_AuditorName" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Auditor Name</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AuditorName" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_AuditorName"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_AuditorName" xlink:to="lab_dei_AuditorName" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_481a4796-067f-4efe-9a06-88888c1b81e9_verboseLabel_en-US" xlink:label="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Less: accumulated depreciation</link:label>
    <link:label id="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_label_en-US" xlink:label="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:to="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityCentralIndexKey_16be8055-9b14-4545-b621-76a458a1d37d_terseLabel_en-US" xlink:label="lab_dei_EntityCentralIndexKey" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity Central Index Key</link:label>
    <link:label id="lab_dei_EntityCentralIndexKey_label_en-US" xlink:label="lab_dei_EntityCentralIndexKey" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Central Index Key</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityCentralIndexKey"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCentralIndexKey" xlink:to="lab_dei_EntityCentralIndexKey" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AllocatedShareBasedCompensationExpense_396780fd-0029-46d6-844f-d2a10f8563fc_terseLabel_en-US" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Compensation expense</link:label>
    <link:label id="lab_us-gaap_AllocatedShareBasedCompensationExpense_label_en-US" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Payment Arrangement, Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllocatedShareBasedCompensationExpense" xlink:to="lab_us-gaap_AllocatedShareBasedCompensationExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsGross_3f1aa979-8c1e-49f4-9a8b-929979250b77_verboseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsGross" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Gross Intangible Assets</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsGross_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsGross" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Gross</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsGross" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsGross" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FederalFundsSoldMaturityTerm_89aef677-5e7a-4454-8caa-9cc76b8d296b_verboseLabel_en-US" xlink:label="lab_isba_FederalFundsSoldMaturityTerm" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Period for federal fund sold</link:label>
    <link:label id="lab_isba_FederalFundsSoldMaturityTerm_label_en-US" xlink:label="lab_isba_FederalFundsSoldMaturityTerm" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Funds Sold, Maturity Term</link:label>
    <link:label id="lab_isba_FederalFundsSoldMaturityTerm_documentation_en-US" xlink:label="lab_isba_FederalFundsSoldMaturityTerm" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Federal Funds Sold, Maturity Term</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FederalFundsSoldMaturityTerm" xlink:href="isba-20231231.xsd#isba_FederalFundsSoldMaturityTerm"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FederalFundsSoldMaturityTerm" xlink:to="lab_isba_FederalFundsSoldMaturityTerm" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestReceivableAndOtherAssets_59b983c7-2894-4a89-af4f-801fc3447ed4_terseLabel_en-US" xlink:label="lab_us-gaap_InterestReceivableAndOtherAssets" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest Receivable and Other Assets</link:label>
    <link:label id="lab_us-gaap_InterestReceivableAndOtherAssets_label_en-US" xlink:label="lab_us-gaap_InterestReceivableAndOtherAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Receivable and Other Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestReceivableAndOtherAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestReceivableAndOtherAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestReceivableAndOtherAssets" xlink:to="lab_us-gaap_InterestReceivableAndOtherAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_3afa5388-7e4c-4e35-8fa9-36a7129524c5_totalLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Other comprehensive income (loss), net of tax</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_InterestPayableFairValueDisclosure_61de0b2d-140a-4fb6-823b-2602b63bcbe2_terseLabel_en-US" xlink:label="lab_isba_InterestPayableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accrued interest payable</link:label>
    <link:label id="lab_isba_InterestPayableFairValueDisclosure_label_en-US" xlink:label="lab_isba_InterestPayableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Payable, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_InterestPayableFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_InterestPayableFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Interest Payable, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_InterestPayableFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_InterestPayableFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_InterestPayableFairValueDisclosure" xlink:to="lab_isba_InterestPayableFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_4051fd7e-150f-4e40-a435-8dbcce21884e_terseLabel_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disaggregation of Revenue [Table Text Block]</link:label>
    <link:label id="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_label_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disaggregation of Revenue [Table Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DisaggregationOfRevenueTableTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:to="lab_us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_RiskRating13Member_6d546973-6998-4c16-a894-d73d8ed7c806_terseLabel_en-US" xlink:label="lab_isba_RiskRating13Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Risk Rating 1-3</link:label>
    <link:label id="lab_isba_RiskRating13Member_label_en-US" xlink:label="lab_isba_RiskRating13Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Risk Rating 1-3 [Member]</link:label>
    <link:label id="lab_isba_RiskRating13Member_documentation_en-US" xlink:label="lab_isba_RiskRating13Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Risk Rating 1-3</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_RiskRating13Member" xlink:href="isba-20231231.xsd#isba_RiskRating13Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_RiskRating13Member" xlink:to="lab_isba_RiskRating13Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues_ac0c38fa-27e3-440d-bf17-6b32e7f04fd0_verboseLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Issuance of common stock</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Value, New Issues</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities_2980b82b-537c-4139-ab2c-996d688c04d7_negatedPeriodStartLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:type="resource" xml:lang="en-US">Accrued benefit cost at January 1</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities_79ecf66c-1fc0-4ef1-bd55-76a5e9aa92db_negatedPeriodEndLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities" xlink:role="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:type="resource" xml:lang="en-US">Accrued benefit cost at December 31</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liability, Defined Benefit Pension Plan</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities" xlink:to="lab_us-gaap_DefinedBenefitPensionPlanCurrentAndNoncurrentLiabilities" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum_d611a4e2-520f-419d-b275-fd6800ecd613_verboseLabel_en-US" xlink:label="lab_isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum percentage of debt servicing over gross income</link:label>
    <link:label id="lab_isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum_label_en-US" xlink:label="lab_isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Debt Servicing To Gross Income Ratio, Maximum</link:label>
    <link:label id="lab_isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum_documentation_en-US" xlink:label="lab_isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable, Debt Servicing To Gross Income Ratio, Maximum</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum" xlink:href="isba-20231231.xsd#isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum" xlink:to="lab_isba_FinancingReceivableDebtServicingToGrossIncomeRatioMaximum" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross_38418c9b-a41c-4106-b88a-cc0b5f7d82fa_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Asset, Debt Securities, Available-for-Sale, Unrealized Loss</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross" xlink:to="lab_us-gaap_DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_a68d85e0-1460-437c-8f09-cdb2ad3fae0d_verboseLabel_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer, Excluding Assessed Tax</link:label>
    <link:label id="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_label_en-US" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue from Contract with Customer, Excluding Assessed Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure_9b15eb74-998b-47ff-8588-f3c9fcc8f394_verboseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum amount of loans</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure" xlink:to="lab_us-gaap_ConcentrationRiskCreditRiskFinancialInstrumentMaximumExposure" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_EntityDomain_f46fe833-a5d7-4611-acd4-9a89dc750ea1_terseLabel_en-US" xlink:label="lab_dei_EntityDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity [Domain]</link:label>
    <link:label id="lab_dei_EntityDomain_label_en-US" xlink:label="lab_dei_EntityDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityDomain" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_EntityDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityDomain" xlink:to="lab_dei_EntityDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentDeferralMember_bb9442ed-f73f-48b8-8397-fc242773aefe_terseLabel_en-US" xlink:label="lab_us-gaap_PaymentDeferralMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Payment Deferral</link:label>
    <link:label id="lab_us-gaap_PaymentDeferralMember_label_en-US" xlink:label="lab_us-gaap_PaymentDeferralMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payment Deferral [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentDeferralMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentDeferralMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentDeferralMember" xlink:to="lab_us-gaap_PaymentDeferralMember" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_AmendmentFlag_c6f53035-2965-4afa-b340-95b6a754e1ad_terseLabel_en-US" xlink:label="lab_dei_AmendmentFlag" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amendment Flag</link:label>
    <link:label id="lab_dei_AmendmentFlag_label_en-US" xlink:label="lab_dei_AmendmentFlag" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amendment Flag</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_AmendmentFlag"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_AmendmentFlag" xlink:to="lab_dei_AmendmentFlag" xlink:type="arc" order="1"/>
    <link:label id="lab_dei_LegalEntityAxis_7520e782-6b89-432b-8db4-02bf44dbc55a_terseLabel_en-US" xlink:label="lab_dei_LegalEntityAxis" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Legal Entity [Axis]</link:label>
    <link:label id="lab_dei_LegalEntityAxis_label_en-US" xlink:label="lab_dei_LegalEntityAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Legal Entity [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LegalEntityAxis" xlink:href="https://xbrl.sec.gov/dei/2023/dei-2023.xsd#dei_LegalEntityAxis"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_LegalEntityAxis" xlink:to="lab_dei_LegalEntityAxis" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax_46ab9502-d940-4ec7-b52c-7fb6a43f3afa_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Reclassification adjustment for net realized (gains) losses included in net income</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets_b23ac066-cc57-47e4-b31d-994c3d2c800b_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Core deposit premium and acquisition expenses</link:label>
    <link:label id="lab_us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets_label_en-US" xlink:label="lab_us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Assets, Goodwill and Intangible Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets" xlink:to="lab_us-gaap_DeferredTaxAssetsGoodwillAndIntangibleAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SubordinatedBorrowingInterestRate_8b6e18b0-806a-4bfa-b6eb-cf668127c040_terseLabel_en-US" xlink:label="lab_us-gaap_SubordinatedBorrowingInterestRate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subordinated Borrowing, Interest Rate</link:label>
    <link:label id="lab_us-gaap_SubordinatedBorrowingInterestRate_label_en-US" xlink:label="lab_us-gaap_SubordinatedBorrowingInterestRate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subordinated Borrowing, Interest Rate</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubordinatedBorrowingInterestRate" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SubordinatedBorrowingInterestRate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubordinatedBorrowingInterestRate" xlink:to="lab_us-gaap_SubordinatedBorrowingInterestRate" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DerivativeAssetFairValueOfCollateral_d9b22cd0-6e5a-4942-abdb-ae74ab718e14_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativeAssetFairValueOfCollateral" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivative Asset, Fair Value of Collateral</link:label>
    <link:label id="lab_us-gaap_DerivativeAssetFairValueOfCollateral_label_en-US" xlink:label="lab_us-gaap_DerivativeAssetFairValueOfCollateral" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative Asset, Fair Value of Collateral</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueOfCollateral" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DerivativeAssetFairValueOfCollateral"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeAssetFairValueOfCollateral" xlink:to="lab_us-gaap_DerivativeAssetFairValueOfCollateral" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestPaidNet_97c97539-9bab-4b9c-a9b6-447d52e4501f_terseLabel_en-US" xlink:label="lab_us-gaap_InterestPaidNet" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest paid</link:label>
    <link:label id="lab_us-gaap_InterestPaidNet_label_en-US" xlink:label="lab_us-gaap_InterestPaidNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Paid, Excluding Capitalized Interest, Operating Activities</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestPaidNet" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestPaidNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestPaidNet" xlink:to="lab_us-gaap_InterestPaidNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_InterestIncomeExpenseNet_5c4de321-1261-43b4-a04e-4d8df8d6fe84_totalLabel_en-US" xlink:label="lab_us-gaap_InterestIncomeExpenseNet" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net interest income</link:label>
    <link:label id="lab_us-gaap_InterestIncomeExpenseNet_label_en-US" xlink:label="lab_us-gaap_InterestIncomeExpenseNet" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Income (Expense), Net</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestIncomeExpenseNet" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_InterestIncomeExpenseNet"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestIncomeExpenseNet" xlink:to="lab_us-gaap_InterestIncomeExpenseNet" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_UnallocatedFinancingReceivablesMember_d96749ae-4587-4579-a536-e29448694401_terseLabel_en-US" xlink:label="lab_us-gaap_UnallocatedFinancingReceivablesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unallocated Financing Receivables [Member]</link:label>
    <link:label id="lab_us-gaap_UnallocatedFinancingReceivablesMember_label_en-US" xlink:label="lab_us-gaap_UnallocatedFinancingReceivablesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unallocated Financing Receivables [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnallocatedFinancingReceivablesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_UnallocatedFinancingReceivablesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnallocatedFinancingReceivablesMember" xlink:to="lab_us-gaap_UnallocatedFinancingReceivablesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent_63384d69-c11f-43fb-b22d-8b6ad808d438_terseLabel_en-US" xlink:label="lab_isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investment of low income housing tax credits, non cash component</link:label>
    <link:label id="lab_isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent_label_en-US" xlink:label="lab_isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment of low income housing tax credits, non cash component</link:label>
    <link:label id="lab_isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent_documentation_en-US" xlink:label="lab_isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Investment of low income housing tax credits, non cash component</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent" xlink:href="isba-20231231.xsd#isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent" xlink:to="lab_isba_InvestmentOfLowIncomeHousingTaxCreditsNonCashComponent" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_CoreDepositsMember_008f435f-3c18-42f5-ab24-8c36aa757c82_verboseLabel_en-US" xlink:label="lab_us-gaap_CoreDepositsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Core deposit premium resulting from acquisitions [Member]</link:label>
    <link:label id="lab_us-gaap_CoreDepositsMember_50f9cff7-20ab-4985-99ca-cc4693d456dc_terseLabel_en-US" xlink:label="lab_us-gaap_CoreDepositsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Core Deposits [Member]</link:label>
    <link:label id="lab_us-gaap_CoreDepositsMember_label_en-US" xlink:label="lab_us-gaap_CoreDepositsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Core Deposits [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CoreDepositsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_CoreDepositsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CoreDepositsMember" xlink:to="lab_us-gaap_CoreDepositsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_IsabellaBankCorporationRestrictedStockPlanMember_559ef6b3-72bc-47c6-bc28-ce99bc4fce6b_terseLabel_en-US" xlink:label="lab_isba_IsabellaBankCorporationRestrictedStockPlanMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Isabella Bank Corporation Restricted Stock Plan</link:label>
    <link:label id="lab_isba_IsabellaBankCorporationRestrictedStockPlanMember_label_en-US" xlink:label="lab_isba_IsabellaBankCorporationRestrictedStockPlanMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Isabella Bank Corporation Restricted Stock Plan [Member]</link:label>
    <link:label id="lab_isba_IsabellaBankCorporationRestrictedStockPlanMember_documentation_en-US" xlink:label="lab_isba_IsabellaBankCorporationRestrictedStockPlanMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Isabella Bank Corporation Restricted Stock Plan</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_IsabellaBankCorporationRestrictedStockPlanMember" xlink:href="isba-20231231.xsd#isba_IsabellaBankCorporationRestrictedStockPlanMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_IsabellaBankCorporationRestrictedStockPlanMember" xlink:to="lab_isba_IsabellaBankCorporationRestrictedStockPlanMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock_ca45dd11-81b8-40c0-8bd4-c3a99db965cb_verboseLabel_en-US" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">MARKETING COSTS</link:label>
    <link:label id="lab_us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock_label_en-US" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Selling, General and Administrative Expenses, Policy [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock" xlink:to="lab_us-gaap_SellingGeneralAndAdministrativeExpensesPolicyTextBlock" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_0449c0ea-e9de-44df-a3bd-c20d77679d48_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Investment return</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets" xlink:to="lab_us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_d3c36094-195b-4c67-a135-3a57b9bdc07d_totalLabel_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Average number of common shares outstanding used to calculate diluted earnings per common share</link:label>
    <link:label id="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_label_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Diluted</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage_66938fc3-88e5-486f-952f-a5dfeb58cb98_terseLabel_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Vesting percentage</link:label>
    <link:label id="lab_us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage_label_en-US" xlink:label="lab_us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage" xlink:to="lab_us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LoansReceivableGrossFairValueDisclosure_375ef800-5474-4164-817c-322cc6226065_verboseLabel_en-US" xlink:label="lab_isba_LoansReceivableGrossFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total loans</link:label>
    <link:label id="lab_isba_LoansReceivableGrossFairValueDisclosure_label_en-US" xlink:label="lab_isba_LoansReceivableGrossFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable, Gross, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_LoansReceivableGrossFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_LoansReceivableGrossFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Loans Receivable, Gross, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LoansReceivableGrossFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_LoansReceivableGrossFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LoansReceivableGrossFairValueDisclosure" xlink:to="lab_isba_LoansReceivableGrossFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesInterestRate_38d53ca8-8ea1-483d-8da1-91940fbdd09e_terseLabel_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesInterestRate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">FHLB advances, rate</link:label>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesInterestRate_label_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesInterestRate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances, Interest Rate</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankAdvancesInterestRate" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalHomeLoanBankAdvancesInterestRate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalHomeLoanBankAdvancesInterestRate" xlink:to="lab_us-gaap_FederalHomeLoanBankAdvancesInterestRate" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_0ffb32a8-3d15-4baa-8d8a-65e226715c97_negatedLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-sale, Realized Gain (Loss)</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_c392efa4-c651-4d4c-83f5-18e9e17dc0c4_terseLabel_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Realized Gain (Loss)</link:label>
    <link:label id="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss_label_en-US" xlink:label="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Available-for-Sale, Realized Gain (Loss)</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss" xlink:to="lab_us-gaap_DebtSecuritiesAvailableForSaleRealizedGainLoss" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery_3438145d-24fb-447e-ae37-44133bef4467_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Allowance for loan losses, Recoveries</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Loss, Recovery</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery" xlink:to="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_12709c66-03f9-43d7-b512-441fce23d383_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Purchases of premises and equipment</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_2675138c-ef74-4aa3-9762-62355a3d3179_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Purchases of equipment and premises</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Property, Plant, and Equipment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:to="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AccountingStandardsUpdate201613Member_2cc4a34d-4003-4370-80fc-369f4464bfd3_terseLabel_en-US" xlink:label="lab_us-gaap_AccountingStandardsUpdate201613Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounting Standards Update 2016-13</link:label>
    <link:label id="lab_us-gaap_AccountingStandardsUpdate201613Member_label_en-US" xlink:label="lab_us-gaap_AccountingStandardsUpdate201613Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Standards Update 2016-13 [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountingStandardsUpdate201613Member" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AccountingStandardsUpdate201613Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingStandardsUpdate201613Member" xlink:to="lab_us-gaap_AccountingStandardsUpdate201613Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_0c31f2bd-00e4-40f8-8b73-dfae746a0707_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year Four</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Four</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_Assets_281f3be4-52be-4740-8aa9-9a2a42ef600e_totalLabel_en-US" xlink:label="lab_us-gaap_Assets" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Assets, Total</link:label>
    <link:label id="lab_us-gaap_Assets_e223e14f-6dab-414a-a874-caa255ed1550_terseLabel_en-US" xlink:label="lab_us-gaap_Assets" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Ending assets</link:label>
    <link:label id="lab_us-gaap_Assets_label_en-US" xlink:label="lab_us-gaap_Assets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_Assets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Assets" xlink:to="lab_us-gaap_Assets" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment_07344e94-044f-45c1-95da-059c4b3ed517_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Collectively evaluated for impairment, ALLL</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment" xlink:to="lab_us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_OtherLosses_1f7f5d81-6c66-445b-ba84-75d4f2611ba1_terseLabel_en-US" xlink:label="lab_isba_OtherLosses" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Losses</link:label>
    <link:label id="lab_isba_OtherLosses_label_en-US" xlink:label="lab_isba_OtherLosses" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Losses</link:label>
    <link:label id="lab_isba_OtherLosses_documentation_en-US" xlink:label="lab_isba_OtherLosses" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Losses</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_OtherLosses" xlink:href="isba-20231231.xsd#isba_OtherLosses"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_OtherLosses" xlink:to="lab_isba_OtherLosses" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LaborAndRelatedExpense_629cad97-cbe2-477e-b1cd-27213a0f40f6_verboseLabel_en-US" xlink:label="lab_us-gaap_LaborAndRelatedExpense" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Compensation and benefits</link:label>
    <link:label id="lab_us-gaap_LaborAndRelatedExpense_9c48bd43-9a44-4cc6-8738-4a1dfca8583f_terseLabel_en-US" xlink:label="lab_us-gaap_LaborAndRelatedExpense" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Labor and Related Expense</link:label>
    <link:label id="lab_us-gaap_LaborAndRelatedExpense_label_en-US" xlink:label="lab_us-gaap_LaborAndRelatedExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Labor and Related Expense</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LaborAndRelatedExpense" xlink:to="lab_us-gaap_LaborAndRelatedExpense" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PlanAssetCategoriesDomain_52ebc07a-0af5-4a2c-8680-ad60ad7ead72_terseLabel_en-US" xlink:label="lab_us-gaap_PlanAssetCategoriesDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Category [Domain]</link:label>
    <link:label id="lab_us-gaap_PlanAssetCategoriesDomain_label_en-US" xlink:label="lab_us-gaap_PlanAssetCategoriesDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Category [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanAssetCategoriesDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PlanAssetCategoriesDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanAssetCategoriesDomain" xlink:to="lab_us-gaap_PlanAssetCategoriesDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_AuctionRatePreferredSecuritiesMember_ff6002de-dd90-4b2e-9b0d-a5cb470b6155_verboseLabel_en-US" xlink:label="lab_us-gaap_AuctionRatePreferredSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Auction rate money market preferred [Member]</link:label>
    <link:label id="lab_us-gaap_AuctionRatePreferredSecuritiesMember_7d44fe1c-54e8-4688-a66a-1a480bbb1da7_terseLabel_en-US" xlink:label="lab_us-gaap_AuctionRatePreferredSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Auction Rate Preferred Securities [Member]</link:label>
    <link:label id="lab_us-gaap_AuctionRatePreferredSecuritiesMember_label_en-US" xlink:label="lab_us-gaap_AuctionRatePreferredSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Auction Rate Preferred Securities [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AuctionRatePreferredSecuritiesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_AuctionRatePreferredSecuritiesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AuctionRatePreferredSecuritiesMember" xlink:to="lab_us-gaap_AuctionRatePreferredSecuritiesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract_db92a739-e22b-464c-9b3d-7117bc3edd10_terseLabel_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Change in unrecognized pension cost on defined benefit pension plan</link:label>
    <link:label id="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract_label_en-US" xlink:label="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:to="lab_us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares_a9071fd1-5e85-4dda-af30-29f07d13eb45_terseLabel_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Eligible shares, total</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares_971f30f1-62e5-4e96-99f6-c6930c0ddf1a_totalLabel_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Eligible shares, total</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares_label_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Common Stock Issued and Reserved for Future Issuance, Shares</link:label>
    <link:label id="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares_documentation_en-US" xlink:label="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Common Stock Issued and Reserved for Future Issuance, Shares</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares" xlink:href="isba-20231231.xsd#isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares" xlink:to="lab_isba_DeferredCompensationArrangementwithIndividualCommonStockIssuedandReservedforFutureIssuanceShares" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_a8d54ba9-d56b-4d39-b1a1-4bdc8b9d43a8_verboseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">FINANCING ACTIVITIES</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_9aea15f3-a866-4c5a-97c8-51e0727df52d_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_d7ef92e8-79c6-4c2c-86e8-c1bd8e43b87d_verboseLabel_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Investment allocation in securities</link:label>
    <link:label id="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_label_en-US" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Target Allocation, Percentage</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:to="lab_us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees_82f27080-c397-43f0-8caf-353870ea3f12_terseLabel_en-US" xlink:label="lab_us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loan underwriting fees</link:label>
    <link:label id="lab_us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees_label_en-US" xlink:label="lab_us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Expense Related to Distribution or Servicing and Underwriting Fees</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees" xlink:to="lab_us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_BankOwnedLifeInsurance_a10c74a3-b944-4935-9d47-8f6a7eb47580_verboseLabel_en-US" xlink:label="lab_us-gaap_BankOwnedLifeInsurance" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Corporate owned life insurance</link:label>
    <link:label id="lab_us-gaap_BankOwnedLifeInsurance_label_en-US" xlink:label="lab_us-gaap_BankOwnedLifeInsurance" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Bank Owned Life Insurance</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BankOwnedLifeInsurance" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_BankOwnedLifeInsurance"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BankOwnedLifeInsurance" xlink:to="lab_us-gaap_BankOwnedLifeInsurance" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_c5c22f5f-d92e-4091-b23f-109fc569d177_verboseLabel_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Average number of common shares outstanding for basic calculation</link:label>
    <link:label id="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_label_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Basic</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:to="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral_c7c2fa1b-d762-40db-8573-76464573cd9a_terseLabel_en-US" xlink:label="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Securities Sold under Agreements to Repurchase, Fair Value of Collateral</link:label>
    <link:label id="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral_label_en-US" xlink:label="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Securities Sold under Agreements to Repurchase, Fair Value of Collateral</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral" xlink:to="lab_us-gaap_SecuritiesSoldUnderAgreementsToRepurchaseFairValueOfCollateral" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_AgriculturalRealEstatePortfolioSegmentMember_394deebe-776f-4721-91f2-36942336c5de_terseLabel_en-US" xlink:label="lab_isba_AgriculturalRealEstatePortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Agricultural Real Estate Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_AgriculturalRealEstatePortfolioSegmentMember_label_en-US" xlink:label="lab_isba_AgriculturalRealEstatePortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Agricultural Real Estate Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_AgriculturalRealEstatePortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_AgriculturalRealEstatePortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Agricultural Real Estate Portfolio Segment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_AgriculturalRealEstatePortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_AgriculturalRealEstatePortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_AgriculturalRealEstatePortfolioSegmentMember" xlink:to="lab_isba_AgriculturalRealEstatePortfolioSegmentMember" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_CommonStockSharesHeldbyRelatedParty_d8d521bf-58df-430c-a9a4-32fe7c242f39_terseLabel_en-US" xlink:label="lab_isba_CommonStockSharesHeldbyRelatedParty" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common Stock, Shares Held by Related Party</link:label>
    <link:label id="lab_isba_CommonStockSharesHeldbyRelatedParty_label_en-US" xlink:label="lab_isba_CommonStockSharesHeldbyRelatedParty" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares Held by Related Party</link:label>
    <link:label id="lab_isba_CommonStockSharesHeldbyRelatedParty_documentation_en-US" xlink:label="lab_isba_CommonStockSharesHeldbyRelatedParty" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Common Stock, Shares Held by Related Party</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_CommonStockSharesHeldbyRelatedParty" xlink:href="isba-20231231.xsd#isba_CommonStockSharesHeldbyRelatedParty"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_CommonStockSharesHeldbyRelatedParty" xlink:to="lab_isba_CommonStockSharesHeldbyRelatedParty" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_ServiceChargesAndDepositAccountFeesMember_d454dc37-a9d5-4755-a60e-c332d4541bbf_terseLabel_en-US" xlink:label="lab_isba_ServiceChargesAndDepositAccountFeesMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Service Charges And Deposit Account Fees [Member]</link:label>
    <link:label id="lab_isba_ServiceChargesAndDepositAccountFeesMember_label_en-US" xlink:label="lab_isba_ServiceChargesAndDepositAccountFeesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Service Charges And Deposit Account Fees [Member]</link:label>
    <link:label id="lab_isba_ServiceChargesAndDepositAccountFeesMember_documentation_en-US" xlink:label="lab_isba_ServiceChargesAndDepositAccountFeesMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Service Charges And Deposit Account Fees [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_ServiceChargesAndDepositAccountFeesMember" xlink:href="isba-20231231.xsd#isba_ServiceChargesAndDepositAccountFeesMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_ServiceChargesAndDepositAccountFeesMember" xlink:to="lab_isba_ServiceChargesAndDepositAccountFeesMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ScheduleOfShortTermDebtTable_2921c2c6-3335-468e-b630-59da1fe38596_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfShortTermDebtTable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Short-term Debt [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfShortTermDebtTable_label_en-US" xlink:label="lab_us-gaap_ScheduleOfShortTermDebtTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Short-Term Debt [Table]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShortTermDebtTable" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ScheduleOfShortTermDebtTable"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfShortTermDebtTable" xlink:to="lab_us-gaap_ScheduleOfShortTermDebtTable" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment_098787a1-c2d0-455b-80ea-2b7d3b8751e1_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Premises and equipment</link:label>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment_label_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Property, Plant and Equipment</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_StateandLocalFundsPurchasedMember_cfa6b526-2ab4-496d-907a-97522c0a2497_terseLabel_en-US" xlink:label="lab_isba_StateandLocalFundsPurchasedMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">State and Local Funds Purchased [Member]</link:label>
    <link:label id="lab_isba_StateandLocalFundsPurchasedMember_label_en-US" xlink:label="lab_isba_StateandLocalFundsPurchasedMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">State and Local Funds Purchased [Member]</link:label>
    <link:label id="lab_isba_StateandLocalFundsPurchasedMember_documentation_en-US" xlink:label="lab_isba_StateandLocalFundsPurchasedMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">State and Local Funds Purchased [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_StateandLocalFundsPurchasedMember" xlink:href="isba-20231231.xsd#isba_StateandLocalFundsPurchasedMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_StateandLocalFundsPurchasedMember" xlink:to="lab_isba_StateandLocalFundsPurchasedMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription_fa155d09-3378-433f-ad6c-7d04ef96e8f8_verboseLabel_en-US" xlink:label="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Reclassifications</link:label>
    <link:label id="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription_label_en-US" xlink:label="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification, Comparability Adjustment [Policy Text Block]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PriorPeriodReclassificationAdjustmentDescription" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_PriorPeriodReclassificationAdjustmentDescription"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PriorPeriodReclassificationAdjustmentDescription" xlink:to="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapital_335b46f2-7541-415e-b9dd-f6646360a160_verboseLabel_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapital" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Actual Amount</link:label>
    <link:label id="lab_us-gaap_TierOneRiskBasedCapital_label_en-US" xlink:label="lab_us-gaap_TierOneRiskBasedCapital" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Banking Regulation, Tier 1 Risk-Based Capital, Actual</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TierOneRiskBasedCapital" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TierOneRiskBasedCapital"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TierOneRiskBasedCapital" xlink:to="lab_us-gaap_TierOneRiskBasedCapital" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_LoanOriginationCommitmentsMember_28355def-2fc9-4882-bdc8-256b24fed3a4_verboseLabel_en-US" xlink:label="lab_us-gaap_LoanOriginationCommitmentsMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Commitments to grant loans [Member]</link:label>
    <link:label id="lab_us-gaap_LoanOriginationCommitmentsMember_label_en-US" xlink:label="lab_us-gaap_LoanOriginationCommitmentsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loan Origination Commitments [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanOriginationCommitmentsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_LoanOriginationCommitmentsMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoanOriginationCommitmentsMember" xlink:to="lab_us-gaap_LoanOriginationCommitmentsMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FinancingReceivableNonaccrualNoAllowance_7e6d0754-4982-457b-8574-498317ce446b_terseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableNonaccrualNoAllowance" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable, Nonaccrual, No Allowance</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableNonaccrualNoAllowance_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableNonaccrualNoAllowance" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable, Nonaccrual, No Allowance</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableNonaccrualNoAllowance" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FinancingReceivableNonaccrualNoAllowance"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableNonaccrualNoAllowance" xlink:to="lab_us-gaap_FinancingReceivableNonaccrualNoAllowance" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_RevenuesAbstract_61820cb0-349e-4fe7-8032-348c8593912f_verboseLabel_en-US" xlink:label="lab_us-gaap_RevenuesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Income</link:label>
    <link:label id="lab_us-gaap_RevenuesAbstract_label_en-US" xlink:label="lab_us-gaap_RevenuesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenues [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_RevenuesAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenuesAbstract" xlink:to="lab_us-gaap_RevenuesAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested_4f5b7d28-b800-4174-8c34-d093fe14cc1e_periodStartLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Beginning balance</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested_5181d11c-2ca5-4db2-8518-57f533eff52a_periodEndLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Ending balance</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueNonvested" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_0b11d3a7-3ceb-4cea-8548-506caf438826_verboseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of estimated amortization expense associated with identifiable intangibles</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_LoansReceivableCollateralizedByOtherInventoryMember_675a86be-5865-4b7a-be2d-17305d95e38a_terseLabel_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByOtherInventoryMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Other Inventory [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByOtherInventoryMember_label_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByOtherInventoryMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Other Inventory [Member]</link:label>
    <link:label id="lab_isba_LoansReceivableCollateralizedByOtherInventoryMember_documentation_en-US" xlink:label="lab_isba_LoansReceivableCollateralizedByOtherInventoryMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Loans Receivable, Collateralized By Other Inventory [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_LoansReceivableCollateralizedByOtherInventoryMember" xlink:href="isba-20231231.xsd#isba_LoansReceivableCollateralizedByOtherInventoryMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_LoansReceivableCollateralizedByOtherInventoryMember" xlink:to="lab_isba_LoansReceivableCollateralizedByOtherInventoryMember" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearThree_6917e354-bd7c-4757-b2d3-14c47f21544f_verboseLabel_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearThree" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Year Three</link:label>
    <link:label id="lab_us-gaap_TimeDepositMaturitiesYearThree_label_en-US" xlink:label="lab_us-gaap_TimeDepositMaturitiesYearThree" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Time Deposit Maturities, Year Three</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeDepositMaturitiesYearThree" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_TimeDepositMaturitiesYearThree"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimeDepositMaturitiesYearThree" xlink:to="lab_us-gaap_TimeDepositMaturitiesYearThree" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member_7634754b-60f4-4266-b227-75bb34633e1c_terseLabel_en-US" xlink:label="lab_isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances, Fixed Rate Due 2024 [Member]</link:label>
    <link:label id="lab_isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member_label_en-US" xlink:label="lab_isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances, Fixed Rate Due 2022 [Member]</link:label>
    <link:label id="lab_isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member_documentation_en-US" xlink:label="lab_isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances, Fixed Rate Due 2022 [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member" xlink:href="isba-20231231.xsd#isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member" xlink:to="lab_isba_FederalHomeLoanBankAdvancesFixedRateDue2022Member" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_StatementLineItems_6f917adf-2158-4722-b559-299bfb4cdcdc_terseLabel_en-US" xlink:label="lab_us-gaap_StatementLineItems" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statement [Line Items]</link:label>
    <link:label id="lab_us-gaap_StatementLineItems_label_en-US" xlink:label="lab_us-gaap_StatementLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement [Line Items]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_StatementLineItems"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementLineItems" xlink:to="lab_us-gaap_StatementLineItems" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_FinancingReceivableModificationsAmortizedCost_4d21955e-f396-4a54-930e-750caa0e328c_terseLabel_en-US" xlink:label="lab_isba_FinancingReceivableModificationsAmortizedCost" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable Modifications Amortized Cost</link:label>
    <link:label id="lab_isba_FinancingReceivableModificationsAmortizedCost_label_en-US" xlink:label="lab_isba_FinancingReceivableModificationsAmortizedCost" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable Modifications Amortized Cost</link:label>
    <link:label id="lab_isba_FinancingReceivableModificationsAmortizedCost_documentation_en-US" xlink:label="lab_isba_FinancingReceivableModificationsAmortizedCost" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable Modifications Amortized Cost</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_FinancingReceivableModificationsAmortizedCost" xlink:href="isba-20231231.xsd#isba_FinancingReceivableModificationsAmortizedCost"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_FinancingReceivableModificationsAmortizedCost" xlink:to="lab_isba_FinancingReceivableModificationsAmortizedCost" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets_bc10a5d4-18bd-4cd4-a7ec-17bee0644ad7_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Core deposit premium and acquisition expenses</link:label>
    <link:label id="lab_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets_label_en-US" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Tax Liabilities, Intangible Assets</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_OtherMortgageServicingRightsFairValueDisclosure_137632db-32f4-404f-83f3-96cbd40b6f88_terseLabel_en-US" xlink:label="lab_isba_OtherMortgageServicingRightsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other Mortgage Servicing Rights, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_OtherMortgageServicingRightsFairValueDisclosure_label_en-US" xlink:label="lab_isba_OtherMortgageServicingRightsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Mortgage Servicing Rights, Fair Value Disclosure</link:label>
    <link:label id="lab_isba_OtherMortgageServicingRightsFairValueDisclosure_documentation_en-US" xlink:label="lab_isba_OtherMortgageServicingRightsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Mortgage Servicing Rights, Fair Value Disclosure</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_OtherMortgageServicingRightsFairValueDisclosure" xlink:href="isba-20231231.xsd#isba_OtherMortgageServicingRightsFairValueDisclosure"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_OtherMortgageServicingRightsFairValueDisclosure" xlink:to="lab_isba_OtherMortgageServicingRightsFairValueDisclosure" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesFixedRate_2a5e65b3-5d38-4144-b034-e2764826b12f_terseLabel_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesFixedRate" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">FHLB fixed rate advances</link:label>
    <link:label id="lab_us-gaap_FederalHomeLoanBankAdvancesFixedRate_label_en-US" xlink:label="lab_us-gaap_FederalHomeLoanBankAdvancesFixedRate" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Federal Home Loan Bank, Advances, Fixed Rate</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankAdvancesFixedRate" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FederalHomeLoanBankAdvancesFixedRate"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FederalHomeLoanBankAdvancesFixedRate" xlink:to="lab_us-gaap_FederalHomeLoanBankAdvancesFixedRate" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_56106caf-6147-4500-a1ee-d4d7744aeb04_terseLabel_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Domain]</link:label>
    <link:label id="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain_label_en-US" xlink:label="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification out of Accumulated Other Comprehensive Income [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:to="lab_us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeDomain" xlink:type="arc" order="1"/>
    <link:label id="lab_us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability_a194068f-c306-4977-a812-de6de52879cd_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Contract Amount</link:label>
    <link:label id="lab_us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability_label_en-US" xlink:label="lab_us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Disclosure, off-Balance-Sheet Risks, Face Amount, Liability</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability" xlink:href="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd#us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability" xlink:to="lab_us-gaap_FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability" xlink:type="arc" order="1"/>
    <link:label id="lab_isba_AgriculturalOtherPortfolioSegmentMember_67e440d3-40cd-4da3-9daa-076c6c8ce16f_terseLabel_en-US" xlink:label="lab_isba_AgriculturalOtherPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Agricultural Other Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_AgriculturalOtherPortfolioSegmentMember_a435cb41-7fb1-4dd4-9c43-cc6090cee19a_verboseLabel_en-US" xlink:label="lab_isba_AgriculturalOtherPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Agricultural other [Member]</link:label>
    <link:label id="lab_isba_AgriculturalOtherPortfolioSegmentMember_label_en-US" xlink:label="lab_isba_AgriculturalOtherPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Agricultural Other Portfolio Segment [Member]</link:label>
    <link:label id="lab_isba_AgriculturalOtherPortfolioSegmentMember_documentation_en-US" xlink:label="lab_isba_AgriculturalOtherPortfolioSegmentMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Agricultural Other Portfolio Segment [Member]</link:label>
    <link:loc xlink:type="locator" xlink:label="loc_isba_AgriculturalOtherPortfolioSegmentMember" xlink:href="isba-20231231.xsd#isba_AgriculturalOtherPortfolioSegmentMember"/>
    <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_isba_AgriculturalOtherPortfolioSegmentMember" xlink:to="lab_isba_AgriculturalOtherPortfolioSegmentMember" xlink:type="arc" order="1"/>
  </link:labelLink>
</link:linkbase>
