21709: Alpha Sender ID is Invalid or Not Authorized for this Messaging Service

The Alpha Sender ID being added to a Messaging Service is invalid or Alpha Sender IDs have not been enabled for this Messaging Service.

• The Messaging Service is not enabled to support Alpha Sender IDs.
• The Alpha Sender ID being added to a Messaging Service is invalid. Alphanumeric Sender IDs may be up to 11 characters. Accepted characters include both upper- and lower-case ASCII letters, the digits 0 through 9, and space: A-Z, a-z, 0-9. They may not be only numbers.

• Follow these steps to verify your Messaging Service is enabled to support Alpha Sender IDs. If it is not, please reach out to Support.
• Verify the Alpha Sender ID you are trying to add to the Messaging Service is valid.

Alphanumeric Sender ID Requirements:

1. Enter between 2 - 11 characters that represent the brand identity of the Sender. You can include upper- and lower-case letters, the numbers 0 - 9, and spaces.
2. Include at least one letter.
3. Do not use ASCII special characters (e.g. #, @).
4. For Saudi Arabia, if you are sending promotional messages, your Sender ID needs to have an '-AD' suffix.