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

Log Level: ERROR

## Description

You have attempted to send a message to an unverified phone number while using a trial account.

To prevent spam, trial accounts can only send messages to phone numbers you've verified with Twilio. You must upgrade your account to remove this restriction.

### Possible causes

You attempted to send a message to a phone number that has not been verified on your trial account.

### Possible solutions

* Verify the phone number you wish to reach via the [Twilio Console](https://1console.twilio.com/us1/develop/phone-numbers/manage/verified). See [Verified recipients](/docs/usage/trials#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](/docs/usage/trials#upgrade-your-account) to remove this restriction.