13245: Dial: Not allowed in this API version

This warning appears when Twilio receives <Dial> in a TwiML session that is running on an API version that does not support that verb. A new TwiML session can be started by a TwiML Application apiVersion, and incoming call handling can also use the apiVersion configured on the called Twilio phone number.

• A TwiML Application is set to apiVersion 2008-08-01, so Twilio starts the session with an older version and the returned TwiML includes <Dial>.
• The Twilio phone number handling an incoming call is configured with an older apiVersion, and your webhook returns TwiML that expects 2010-04-01 behavior.
• The webhook or TwiML Bin serving the call returns <Dial> even though the current session version only supports older TwiML verbs.

• Update the TwiML Application apiVersion to 2010-04-01.
• If the warning occurs on an incoming call to a Twilio phone number, update that number's apiVersion to 2010-04-01.
• Review the TwiML returned by your Voice URL and remove <Dial> until the session is running on a supported API version, or return only verbs supported by the selected version.
• Verify that the call is reaching the intended Voice URL or TwiML Application so the session starts with the configuration you expect.

• TwiML™ Voice: <Dial>
• REST API: Applications
• IncomingPhoneNumber resource