5. API Errors
| Code | Meaning |
|---|---|
| 200 | Request completed. |
| 201 | PayIn or PayOut created. |
| 401 | API key, timestamp, or signature is invalid. |
| 404 | PayIn or PayOut with the supplied external_id was not found. |
| 422 | Request validation or business-rule error. |
| 429 | Rate limit exceeded. |
| 500 | Internal server error. |
For an EPT VND PayIn, Invalid paymentData includes details for invalid or missing paymentData.account_number, paymentData.holder, and paymentData.bank_code.
For an EPT VND PayOut, validate the required recipient fields: card_number, paymentData.bank_code, and paymentData.holder. paymentData.bank_code must be one of the values in Bank Codes.