If an API request fails, start with its HTTP status and response body. The error message can explain what needs attention.
Check the request
Open the documentation for the endpoint you are calling. Confirm the server URL, path, HTTP method, and required parameters.
Check the authentication method and access requirements. Some operations require a current signed-in session rather than an API key.
Compare the response with the endpoint's documented errors. Ensure your HTTP client lets you read response bodies for failed requests.
If you are requesting market or blockchain data, confirm the exchange, market, chain, asset, address, and time range are appropriate for that endpoint.
See the API error reference for documented codes and the blockchain troubleshooting reference for address and historical-data errors.
Decide what to check next
Response | Next step |
400 | Check the request format and required input against the endpoint documentation. |
401 | Check the required authentication method and whether your credential or session is current. |
403 | Check whether your account can perform the operation and whether further verification or another access requirement applies. |
404 | Check the endpoint and resource identifier. |
429 | Reduce request frequency and bursts. Review the rate-limit guidance before retrying. |
500 | Keep the error and request details so Support can investigate. |
Use the endpoint-specific response message for additional context. If a code is not listed here, check the reference or contact Support rather than guessing.
Take care before retrying a transaction
A timeout or failed response does not by itself establish whether a money-moving request took effect. Check the transaction or ask Support before submitting the action again. Do not send another payment simply because a status has not updated.
Send a useful support request
Contact Support and include:
The endpoint and HTTP method.
The approximate request time and time zone.
The HTTP status and exact error message.
A request or transaction reference, if available.
What you expected and a small, sanitized example that demonstrates the problem.
Remove credentials, cookies, identity documents, and unrelated personal or financial information. If a sensitive record is needed, ask Support how to submit it securely.