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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentrations and Credit Risk (Details) | 6 Months Ended |  |
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Mar. 31, 2025 USD ($) customer item | Mar. 31, 2024 item customer | Mar. 31, 2023 item customer | Mar. 31, 2025 CNY (¥) customer item | Mar. 31, 2025 HKD ($) customer item | Sep. 30, 2024 USD ($) | Sep. 30, 2024 CNY (¥) | Sep. 30, 2024 HKD ($)
Concentration Risk |  |  |  |  |  |  |  |
Cash and cash equivalents, certificates of deposit and restricted cash were on deposit at financial institutions not subject to insured | $ 8,981,076 |  |  |  |  | $ 6,902,275 |  |
Cash and cash equivalents deposited in financial institutions | 733,672 |  |  |  |  | 1,058,635 |  |
Cash and cash equivalents deposited in financial institutions annual limit | 65,000 |  |  |  | $ 500,000 | 65,000 |  | $ 500,000
Cash deposited in FI insured by FDIC | $ 981,801 |  |  |  |  | $ 1,856,344 |  |
Cash equivalents and restricted cash protection | ¥ |  |  |  | ¥ 500,000 |  |  | ¥ 500,000 |
Customer | Revenue |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Number of customers | customer | 2 | 2 | 2 | 2 | 2 |  |  |
Customer | Purchases |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Number of vendors | item | 2 | 2 | 0 | 2 | 2 |  |  |
Customer | Accounts Receivable |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Number of customers | customer | 2 | 2 |  | 2 | 2 |  |  |
Number of vendors | item | 1 | 0 |  | 1 | 1 |  |  |
Customer | Customer One | Revenue |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Concentration risk (in percent) | 16.00% | 16.00% | 16.00% |  |  |  |  |
Customer | Customer One | Accounts Receivable |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Concentration risk (in percent) | 35.00% | 58.00% |  |  |  |  |  |
Customer | Customer Two | Revenue |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Concentration risk (in percent) | 11.00% | 14.00% | 15.00% |  |  |  |  |
Customer | Customer Four | Accounts Receivable |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Concentration risk (in percent) | 32.00% | 15.00% |  |  |  |  |  |
Supplier | Supplier One | Purchases |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Concentration risk (in percent) | 16.00% | 13.00% | 10.00% |  |  |  |  |
Supplier | Supplier One | Accounts Payable |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Percentage of accounts payable outstanding from transaction with supplier | 47.00% | 10.00% |  |  |  |  |  |
Supplier | Supplier Two | Purchases |  |  |  |  |  |  |  |
Concentration Risk |  |  |  |  |  |  |  |
Concentration risk (in percent) | 10.00% | 13.00% |  |  |  |  |  |

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