Blue messages

[Heavenlyhydra]

So I recently got my phone back from getting fixed and for some reason I can’t get my messages back to blue. We both have Samsung. I have the s20 ultra and he has the s 20 note. Our messages were blue before hand but now they aren’t and I have gone through all the setting and even reset them to make sure. 
He still has sprint and I got a new SIM card for T-Mobile since sprint change to T-Mobile however he hasn’t been able to get his sprint SIM card change. 
how can I return our messages to blue?

[Heavenlyhydra]

Oh and I have read about the chat settings but it’s different with this phone. It’s not like my older phones where I just turn on the rcs. Im not sure how to turn it on for my s20

[strawberry cake]

hello @Heavenlyhydra 

simply use Google Messages app as your default text message app, you may download from Play Store, with default RCS too

ta😉

[Deano89]

see if enabling this in settings》 connections》 more connection settings works for you