Message couldn't be delivered

Message couldn't be delivered to the destination number you are trying to reach temporarily.

• This is because Twilio has identified potential fraudulent messages being sent to the destination you are trying to reach.
• Hence SMS traffic can not be delivered to the destination phone number used for the next couple of hours. The traffic should return to normalcy post that. However, the SMS traffic could be undelivered for an even longer period if fraudulent activity doesn't subside & continues to go on.

You do not need to take any specific action. The disruption in traffic is usually temporary and will resolve in a couple of hours if we do not detect additional fraudulent activity.

Twilio's support team can help investigate what went wrong with delivering your message. Please collect 3 or more message SIDs in your SMS logs from the last 24 hours that were flagged with Error 30453, and open a support request.

Alternatively, you can use the optional RiskCheck parameter when creating a Message with the Programmable Messaging API. To prevent a known/legitimate message from getting blocked in future by SMS Pumping Protection, include the RiskCheck parameter with value disable when creating the new Message resource.

You can also mark known/legitimate phone numbers using the Global Safe List feature so that they don't face any disruption . This provides an additional safety net against false positives, so that the traffic to this number never faces the above scenario. Add known phone numbers to the Safe List by using the Global Safe List API.