14105: Invalid statusCallback attribute

Twilio returns this warning when the <Message> verb includes a statusCallback attribute that is not a valid URL. The statusCallback attribute accepts a relative or absolute URL. If you use an absolute URL, it must contain a valid hostname and the hostname cannot include underscores.

• The <Message> verb includes a statusCallback value that is empty, malformed, or not formatted as a relative or absolute URL.
• The statusCallback value uses an absolute URL with an invalid hostname. This includes hostnames that contain underscores.
• The callback URL contains a typo, incorrect domain, or invalid path. (help.twilio.com)

• Update the statusCallback attribute so it contains a valid relative URL or a fully qualified absolute URL.
• If you use an absolute URL, make sure the hostname is valid and remove any underscores from the domain name.
• If you need a custom status webhook for <Message>, set both statusCallback and action to the same URL. This helps you avoid undefined behavior across message types while Twilio normalizes attribute handling.
• Test the callback URL with a temporary public webhook endpoint to confirm Twilio can send requests successfully, then switch back to your production endpoint after the test passes. (help.twilio.com)

• TwiML Message: <Message>
• Track the Message Status of Outbound Messages
• How to Test and Troubleshoot Twilio Messaging StatusCallback Failures