Issue

Outbound voice calls placed to +1 phone numbers fail or are blocked at Twilio. The API or call logs return one of the following error codes:

• 21216
• 13225
• 32203

Environment

Twilio Console

Cause

To align with FCC regulations, state Attorneys General anti-robocall principles, and carrier partner guidelines, Twilio enforces Primary Customer Profile (PCP) requirements for outbound +1 calls.

In parallel, Twilio is reducing SHAKEN/STIR "C" attestation levels. Without an approved PCP, the account lacks a SHAKEN/STIR bundle, resulting in un-attested or low-attestation traffic that US carriers block.

• Without an approved PCP, no SHAKEN/STIR profile exists, and outgoing calls carry no or low attestation (Level C).
• Associating Twilio phone numbers with an approved PCP and STIR/SHAKEN Trust Product ensures calls carry Attestation Level A, satisfying carrier requirements.

Resolution

• Business Primary Customer Profile (preferred), OR
• Individual Primary Customer Profile with a US Contact (US Phone Number, US Address, & company email ID) in the bundle (if the customer cannot create a Primary Business Profile).

1. Submit the profile for vetting.
2. Assign Phone Numbers & STIR/SHAKEN (Recommended):
   • Assign phone numbers to the approved Primary Customer Profile and the STIR/SHAKEN Trust Product to receive Level A attestation:
     • Once you've created a Customer Profile, click "View Profile", then go to the "Assigned phone numbers" tab.
     • Click "Assign Phone Numbers", then select the numbers you want to assign to your Customer Profile.
     • Assign phone numbers to the STIR/SHAKEN Trust Product to receive Level A attestation.

Additional Information

• Parent vs. Subaccounts: Only the parent account requires an approved PCP. Subaccount traffic automatically inherits compliance from the parent account.
• Please reach out Twilio Support for additional assistance.