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# HTTP Status Codes

**HTTP Status Code Table**

| Status code | Error                  | Description                                                                                  | Solution                                                                                                                                        |
| ----------- | ---------------------- | -------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------- |
| **400**     | Bad Request            | The request is not understood by the system due to incorrect syntax.                         | Verify that all request parameters are correct and that none of the mandatory ones are missing.                                                 |
| **401**     | Unauthorized           | The access token is missing or invalid/expired.                                              | Check if a valid token has been generated and that it is correctly sent in the Authorization header.                                            |
| **403**     | Forbidden              | Access is restricted for the IP or authentication data used.                                 | Ensure that the Project is active, properly configured, and that the IP is on the allowed list.                                                 |
| **404**     | Not Found              | The requested resource was not found.                                                        | Verify the endpoint URL and the resource identifier parameter (e.g., qrId) for correctness.                                                     |
| **405**     | Method Not Allowed     | The HTTP method used (GET, POST, etc.) is not allowed on this endpoint.                      | Make sure you are using the correct HTTP method as specified for that endpoint.                                                                 |
| **409**     | Conflict               | A data conflict occurred (e.g., a QR with the same parameters already exists).               | Check the application logic to avoid sending repeated or contradictory data.                                                                    |
| **415**     | Unsupported Media Type | The content of the request is not in a format accepted by the API.                           | <p>Verify that the <code>Content-Type</code> header is set to <code>application/json</code></p><p>and that the body is correctly formatted.</p> |
| **422**     | Unprocessable Entity   | The sent data is valid in format but cannot be processed due to logically incorrect content. | Check the transmitted values (e.g., amount, currency, custom parameters) to comply with validation rules.                                       |
| **429**     | Too Many Requests      | Too many requests in a short period of time.                                                 | Implement a retry mechanism with backoff, and if necessary, contact the support team to configure custom policies.                              |
| **500**     | Internal Server Error  | An unexpected internal error occurred in the system.                                         | Try again after a few moments. If the problem persists, contact the support team with request details.                                          |
| **503**     | Service Unavailable    | The API is temporarily unavailable due to overload or maintenance.                           | Try again after a few minutes. If the unavailability persists, check official notifications or contact technical support.                       |