> ## Documentation Index
> Fetch the complete documentation index at: https://developer.fin.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Technical Integration

> FAQs regarding API integration, sandbox testing, and technical capabilities.

<AccordionGroup>
  <Accordion title="Why am I getting 'unsupported beneficiary currency and scheme combination' when initiating a USD payout?">
    While the beneficiary was created successfully, you should have also received a `liquidation_address` in the response.

    For **USD payouts**, the Transfer API and Batch API are **not applicable** for local routes. If the beneficiary has `auto_settlement: false` with country `USA` and currency `USD`, using those APIs will result in this error. The Transfer/Batch APIs can only be used for USD SWIFT in specific cases where Fin maintains an underlying prefunding with the banking partner.

    **All USD local payouts must go through the `liquidation_address`.** You need to send **USDC on Polygon** (the currently supported currency and rail — more are being added) to the `liquidation_address`. This automatically triggers a liquidation address drain, which initiates a payout to the end bank account.

    You will also receive a `transaction.status` webhook when funds are received by Fin at the liquidation address.

    <img src="https://mintcdn.com/fincom/JrEveCpnz-DvgBx5/images/liquidation_address_flow.png?fit=max&auto=format&n=JrEveCpnz-DvgBx5&q=85&s=b0c171e68994d8b05e9aaf21a11e8b18" alt="Liquidation Address Flow" width="4800" height="3300" data-path="images/liquidation_address_flow.png" />
  </Accordion>
</AccordionGroup>