Can't receive International text message

I have a iPhone 11 pro, my friends lived out side of US tried to send me text message ( SMS ), they know the dialing pattern to US, but I never receive those messages. Send text message to them, they didn't get it either. 

This issue not just happened to me, my friends lived in US, also using Xfinity Mobile, have the same issues, anyone know how to fix this issue?

Thanks very much.