Common Error Codes
Local Mail uses standard HTTP status codes to indicate the success or failure of an API request.
Generally speaking, codes in the 2xx range indicate that a request was successfully processed and codes in the 4xx range indicate that there was an error that resulted from the information provided (e.g., authentication, no balance or a missing or wrong parameter).
In case of an error, the body of the response includes a JSON formatted response that tells you exactly what is wrong.
HTTP Status Codes for API
API specific Error Reason/status