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Loans - Summary of loans (Details) - USD ($) | Jun. 30, 2025 | Jun. 30, 2024
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Loans and Leases Receivable Disclosure [Line Items] |  |
Interest receivable | $ 667,686 | $ 597,768
Total loans | 202,571,000 | 185,292,000
Deferred loan fees | (67,000) | (47,000)
Allowance for loan losses | (1,708,269) | (1,797,116)
Loans, net | 200,796,000 | 183,448,000
Provision for loans |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Interest receivable | 603,309 | 513,782
Commercial real estate | Commercial real estate |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 91,867,000 | 74,316,000
Commercial | Commercial and industrial |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 3,876,000 | 5,158,000
Commercial | Construction |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 733,000 | 1,313,000
Residential | One-to-four-family residential |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 56,330,000 | 57,808,000
Residential | Multi-family real estate |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | 47,808,000 | 45,088,000
Consumer Loans | Consumer |  |
Loans and Leases Receivable Disclosure [Line Items] |  |
Total loans | $ 1,957,000 | $ 1,609,000

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