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

# Error Codes

> Summarizes common GatePay error codes, their meanings, and recommended handling actions.

| HTTP Status | Error Code | Description | Solution |
| - | - | - | - |
| `500` | `300000` | System error | System exception, please retry with the same parameters |
| `500` | `300001` | Internal error | System exception, please retry with the same parameters |
| `500` | `400000` | Unknown error | System exception, please retry with the same parameters |
| `200` | `400001` | Request parameter format error | Check request data parameters and format |
| `200` | `400002` | Signature verification failed | Check if the merchant's signature is correct |
| `200` | `400003` | Request timestamp timed out | Check the timestamp field in the request header |
| `200` | `400004` | API identity key invalid | Check whether the `GatePay-Api-Key` request header is configured correctly |
| `200` | `400005` | Client identifier invalid | Check whether the `GatePay-Client-Id` request header is configured correctly |
| `200` | `400007` | Unsupported media type | Check the media type set in the interface |
| `200` | `400020` | Signature random number error | Please check whether the random number is empty |
| `200` | `400201` | Merchant order number already exists | Please verify whether the merchant order number has been submitted repeatedly |
| `200` | `400202` | Order does not exist | Check whether the order has been traded or whether the order number is correct |
| `200` | `400203` | Merchant number does not exist | Check whether the merchant number is correct |
| `200` | `400204` | Order status is incorrect | Check whether the order has expired, canceled, or closed, and use the query interface if necessary |
| `200` | `400205` | Invalid currency | Check the currency type of the order |
| `200` | `400304` | Refund ID does not exist | Check the requested refund ID |
| `200` | `400305` | Merchant channel information does not exist | Check whether `channelId` is correct and not deleted |
| `200` | `400603` | Order timed out | Please verify whether the order has expired |
| `200` | `400604` | Invalid refund-related transaction order | Check whether the refund transaction order is in a completed state |
| `200` | `400605` | Insufficient balance in the payment account | Insufficient balance in the payment account |
| `200` | `400607` | Too many refunds | The number of refunds exceeds the limit |
| `200` | `400608` | Refund amount exception | Please check the refund amount |
| `200` | `400620` | Duplicate order payment | Please verify whether the merchant order number has been submitted repeatedly |
| `200` | `400621` | Incorrect payment amount | Check the requested amount |
| `200` | `400622` | Exchange rate fluctuations result in payment failure | You can try to apply again |
| `200` | `400623` | Unsupported currency payment | Check the payment currency |
| `200` | `400624` | Invalid order status notification address | Check whether the callback address provided by the merchant is valid |
| `200` | `400701` | An active subscription already exists for the same user and product | Please confirm whether an active subscription already exists for the same product |
| `200` | `400702` | Merchant has not enabled channel payment permission | Please confirm whether the merchant has enabled the corresponding channel payment permission |
| `200` | `500008` | Corresponding merchant not found | Check whether the requested merchant ID is correct |
| `200` | `500100` | Payment QR code expired | Reorder and generate a new QR code |
| `200` | `500101` | Duplicate payment QR code | Please verify the order status |
| `200` | `500103` | Address payment exchange currency error | Exchange rate fluctuations affect the conversion |
| `200` | `500203` | Unable to query order details for address payment | Please check whether the address is correct |
| `200` | `500204` | Invalid recipient ID for refund transaction order | Please confirm that the recipient of the refund is a Gate user |
| `200` | `500205` | Refund currency does not match | Please ensure that the refund currency is one of the order currency or the user's payment currency |
| `200` | `500206` | Refund amount exceeds limit | Please check the refund amount of the order |
| `200` | `500207` | Unable to find the refund order for address payment | Please confirm whether the refund was successful or check whether the address is correct |
| `200` | `500208` | Cannot refund orders without a converted address | Please confirm the type of refund order |
| `200` | `550307` | OTC transaction limit exceeded | Please add additional information through the following page to increase your limit: [https://www.gate.com/otc/global\_apply/add\_info](https://www.gate.com/otc/global_apply/add_info) |
| `200` | `550008` | Subaccount status abnormal | Retry later with the same parameters; contact support if the failure persists |
| `200` | `550018` | Risk control engine rejected this transaction | Check the transaction characteristics or contact operations |
| `200` | `550020` | Source IP / region is on the sanctions list | Please switch to a compliant network environment |
| `200` | `550143` | Surcharge amount is invalid | Adjust the surcharge to a non-negative value that does not exceed the configured upper limit |
| `200` | `550200` | Institution delegate permission insufficient | Confirm whether `X-GatePay-On-Behalf-Of` is passed and the request is made under your own merchant identity |
| `200` | `550203` | Tolerance amount is invalid | Ensure the tolerance amount is >= 0 and less than the payable amount |
| `200` | `550205` | Amount precision is invalid | Check whether the decimal precision of the order amount and surcharge meets requirements |
| `200` | `5502724` | Channel name contains invalid characters | `channelId` only allows Chinese, English letters, numbers, underscores, hyphens, and spaces; remove special characters and retry |
| `200` | `5502740` | Subaccounts do not support creating orders | Use the main account or an account with the appropriate permissions |
| `200` | `5502761` | Request conflict | Use a different merchant order number, or retry idempotently with the same parameters |
| `200` | `5504080` | Security item change limit exceeded within 24h | Please wait 24 hours after the security item change before retrying |


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