13807: Client Notification URL Error Response

The Client Notification URL returned an error.

• Your URL is returning 5xx error due to an internal server issue
• Your URL is returning a 400, 401, or 403 due to a server misconfiguration or authentication/authorization issue
• Your URL returned a 404 due to a misconfiguration of your clientNotificationUrl in your TwiML or API request
• Your URL returned a 404 because your application could not find a binding for the user receiving the call

• Resolve your server errors
• Reconfigure your clientNotificationUrl to the correct URL
• Remove the user who has no binding from your call routing
• Return a 200 OK
• Verify you are using Client Call Notification Webhook correctly