30122: Fallback URL is invalid

This error occurs when the fallback URL configured for a Messaging Service or incoming phone number is not a valid URL. Twilio requests the fallback URL when it can't retrieve or execute TwiML from the primary inbound request URL, and the fallback URL must be valid.

• The fallbackUrl value is malformed or cannot be parsed as a valid URL. Twilio expects a valid URL for this setting.

• Replace fallbackUrl with a valid URL and save the Messaging Service or phone number configuration again. Twilio accepts any valid URL for this field.
• If you want to use a Twilio-hosted destination, point the fallback URL to a Studio Flow, TwiML Bin, or Twilio Function webhook URL.
• Set the fallback URL in the Messaging Service fallbackUrl field or in the phone number's Messaging Configuration, depending on where you manage inbound routing.

• Services resource
• Availability and Reliability