Why can I receive texts but can’t send texts?

[Android Central Question]

While at work in a different city, my phone works fine. While at home, I can send picture messages. I can receive texts and picture texts. But, I cannot send simple texts. Samsung Galaxy S9+ with AT&T service

 

[B. Diddy]

Welcome to Android Central! What happens when you try to send regular SMS messages at home? Do you get an error message?

Did you get your S9+ from AT&T, or did you get it unlocked from somewhere else and brought it to AT&T?