# 30034: US A2P 10DLC - Message from an Unregistered Number

Log Type: APPLICATION

Log Level: ERROR

## Description

Twilio blocks messages to U.S. numbers when you send from a +1 10DLC number that is not associated with an approved A2P 10DLC Campaign. To send application-to-person traffic over a U.S. long code, complete A2P 10DLC registration and make sure the number is attached to the Messaging Service associated with your approved Campaign.

### Possible causes

* You sent a message to a U.S. number from a +1 10DLC number that is not associated with an approved A2P 10DLC Campaign.
* Your Brand or Campaign registration is not complete, so the number is still unregistered for U.S.-bound 10DLC traffic.
* The phone number is not in the Sender Pool of the Messaging Service linked to your approved Campaign.
* You added multiple +1 10DLC numbers to a Sole Proprietor Campaign. Only one 10DLC number can be registered for that Campaign. Additional numbers remain unregistered.

### Possible solutions

* Complete A2P 10DLC registration for your Brand and Campaign before sending messages to U.S. numbers from a +1 10DLC number.
* Add the phone number to the Sender Pool of the Messaging Service associated with your approved Campaign.
* Verify the number's A2P registration status. If the number is still unregistered, update the Messaging Service and Campaign association so the number is linked to a verified Campaign.
* If you use a Sole Proprietor Campaign, keep only the single +1 10DLC number you want to use in that Messaging Service.
* If you need to send before 10DLC registration is complete, use a sender type that is not part of A2P 10DLC, such as a Toll-Free number, short code, or Twilio Verify for verification use cases.

#### Additional resources

* [Programmable Messaging and A2P 10DLC](/docs/messaging/compliance/a2p-10dlc)
* [Direct Standard and Low-Volume Standard Registration Guide](/docs/messaging/compliance/a2p-10dlc/direct-standard-onboarding)
* [Troubleshooting A2P Phone Number registration issues](/docs/messaging/compliance/a2p-10dlc/troubleshooting-a2p-brands/troubleshooting-a2p-phone-number-registration-issues)