# 30122: Fallback URL is invalid

Log Type: APPLICATION

Log Level: ERROR

## Description

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.

### Possible causes

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

### Possible solutions

* 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.

#### Additional resources

* [Services resource](/docs/messaging/api/service-resource)
* [Availability and Reliability](/docs/usage/security/availability-reliability)