S10e - MMS Not Working

[Guest]

I have a Galaxy S10e that was originally purchased through T-Mobile. It has since been unlocked and transferred to Verizon. It works in every respect except the ability to send pictures or do group chats (MMS). It can receive pictures but cannot send. I don't understand why this is so. I know that Verizon is CDMA and T-Mobile is GSM and supposedly they don't play nice, but the phone's model (despite being T-Mobile) says it's compatible with Verizon's network. And calls and other forms of text work flawlessly. So what gives? Even on WiFi it doesn't work!

 

I suspect something with the APN settings but the ones I found online already match what the phone has, so I'm confused as to why this is not working. Any help would be appreciated.

[Guest]

Found the problem. Apparently, when on T-Mobile the software for the default Samsung text messaging app was tied to their network for whatever reason. When I switched to the Verizon messaging app, everything suddenly started working. Go figure.