SMS configuration help

Your software
My Mautic version is:
My PHP version is: 8.0.29
My Database type and version is: 10.6.12-MariaDB-0ubuntu0.22.04.

Your problem
My problem is: SMS messages are not being sent. I’ve set up a campaign and trigger to a simple test segment. The Channels:Text Messages panel shows “1 sent” however the text is never received.

These errors are showing in the log:

AH01071: Got error ‘PHP message: PHP Warning: Trying to access array offset on value of type null in /var/www/mautic/app/bundles/SmsBundle/Form/Type/SmsSendType.php on line 75’, referer:

Steps I have tried to fix the problem:
Ensured php-curl is installed
Ensured Twilio token and ID are set correctly
Ensured console mautic:messages:send is run in the cron

Figured it out. I looked at the logs in Twilio and found that the messages are not being delivered because the phone number had not gone through “A2P 10DLC registration”. I submitted the number for registration and am awaiting response.