13803: SMS verb not supported in this realm

This error occurs when you use the <Message> TwiML verb in a Twilio Region that does not support it. <Message> is currently supported only in the default US1 region. It is not available in IE1 or AU1.

• You used <Message> in IE1 or AU1, where that TwiML verb is not currently supported.
• Your application depends on a feature that is not available in the selected Twilio Region. Twilio Regions operate in isolation, so unsupported products and features do not work in the target Region.

• Run the <Message> step in the default US1 region, where Twilio currently supports it.
• If your application must use IE1 or AU1, remove or redesign the <Message> step so the flow uses only features supported in that Region.
• Confirm your Region selection before deployment and verify that every product and TwiML verb used in the flow is supported in that Region.

• Error and Warning Dictionary
• TwiML Message: <Message>
• Regional product availability