Hello @Esme193,
Sorry to hear that.
I believe this is down to iMessage and needing to update the number.
1) Turn off iMessage (Settings > Messages)
2) Restart your phone (by pressing and holding the on/off button)
3) Tap Settings > Phone > My Number and confirm that it is correct.
4) If it is not correct, please enter the correct number
5) Turn iMessage back to On (Settings > Messages)
6) Finally, go to Settings > Messages > Send & Receive and see if the correct number is displayed under “Start new conversations from:”.
This should fix the issue with the texts but if it doesn’t, or you still can’t receive these OTP messages, please let us know.
Mohammed