21608: The 'to' phone number provided is not yet verified for this account.

You have attempted to send a message to an unverified phone number while using a trial account or an account without an approved primary compliance profile (PCP).

To prevent spam, trial accounts and accounts without an approved PCP can only send messages to phone numbers you've verified with Twilio. You must upgrade your account and submit an approved primary compliance profile to remove this restriction.

• You attempted to send a message to a phone number that has not been verified on your trial account.
• Your account doesn't have an approved primary compliance profile, which is required for unrestricted messaging.

• Verify the phone number you wish to reach via the Twilio Console. See Verified recipients for details on trial verification limits. Note that you will need access to this device to receive the call or text with your verification code.
• Upgrade your account and create an approved primary compliance profile to remove this restriction.