Programmable Messaging | Aug. 07, 2025

[U.S. A2P 10DLC] Brand Registration - Authentication+ 2FA Verify & New Error Codes

We’ve made a key improvement to Authentication+ to support programmatically triggering a new 2FA verification email for A2P 10DLC Brand registrations that have failed. 

Alongside the endpoint, we’re introducing a set of dedicated 2FA error codes that surface precise failure reasons and point you to the fastest remedy, so your users can complete brand verification with fewer support tickets and less manual work.

To learn more about Authentication+, check out our Support Article and Twilio API Docs.
 

Error Code

Message

Description

21736

Domain Ownership Could Not Be Verified

The domain used in the brand contact email could not be independently verified.

21737

2FA Verification Expired

The 2FA verification link or token expired before being used.

21738

2FA Email Undeliverable

The verification email could not be delivered to the brand contact.

21739

2FA Verification Failed or Timed Out

The verification process was not completed.

21740

Invalid Brand Contact Email Domain

The domain used for the brand contact email is not acceptable for Authentication+ (e.g., gmail.com).

21741

2FA Code Expired

The verification code was not entered in time.

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