Why have my messages failed to send? May 02, 2022 04:58 Updated Typically messages will fail to send because either the mobile number of the intended recipient(s) is invalid. The recommended format for mobile numbers is to include the international prefix (dial code) and no non-numerical characters such as brackets: Correct: +61412345678 Incorrect: (0061) 0412 345 678 If your numbers are all saved in the correct format, then there is a chance that the number itself is invalid/not in use, or that the sender ID (when sending from a number as opposed to an alpha tag) has been blocked by the recipient. There is also the possibility that the carrier themselves are experiencing issues which could impact your messages being sent successfully. If you are still unsure as to why your messages are failing, email support at support@messaging.tpgtelecom.com.au Related articles Contacts API Contacts V2 | Exporting Contacts SMS Compliance & Best Practice | New Zealand Can I still report on a sub-account that I deactivate? Where do my inbound messages go?