The server is currently unable to handle the request due to a temporary overloading or maintenance of the server. This error can also be caused by the Application SID provided in the access token pointing to an inaccessible URL.
The server is under maintenance.
The Application SID provided in the access token points to an inaccessible URL.
Please check the Application SID URL. For further assistance, please reach out to Twilio Support through the Console or Help Center.