Android Phone Not Receiving Text Messages After Switching to T-Mobile Network

syaoran wrote:

What SMS/MMS messaging app are you using?  Google Messages is what Samsung supports as Samsung Messages has been discontinued for the North American market.  Make sure RCS is enabled in Google Messages. 

Thanks for the quick reply!

I'm currently using the default Google Messages app, and I just checked to confirm that RCS is enabled. I also went through the chat features setup, and it shows as "Connected." However, the issue with delayed or missing messages persists.

Do you think it could be related to the SIM activation or any specific T-Mobile network settings? Or should I try reinstalling Google Messages or switching RCS off and on again?

Appreciate any other suggestions you might have!