I will try to keep this brief and targeted, because I would like a resolution to this problem.
Sometime around 6 weeks or more ago, I switched my Sprint phone to the T-Mobile Network Experience (TNX) by going into a T-Mobile corporate store and having them put it through the paces. I walked out with my new T-Mobile SIM in the phone and my Sprint SIM in my hand as a backup, in case TNX goes awry.
I only have a weak roaming signal at work. It’s because of the type of building I’m in. I realized over the course of a couple days that T-Mobile doesn’t have the same roaming agreements as Sprint. So while I was still showing that same weak signal, my phone with the T-Mobile SIM installed would no longer register on the roaming network (AT&T I think).
I contacted customer support and had them switch me back to my Sprint SIM, because I really do need to be able to at least send/receive texts at work. All went fine, but I realized that T-Mobile Tuesdays no longer works. It won’t let me register my number. The other two lines on my account work fine (didn’t switch them to TNX), and I can register those numbers with this phone, but I get an error message when I try to register the number that went Sprint→ TNX → Sprint.
I got on Reddit, and apparently this is a known issue. Everyone who has gont from TNX back to their Sprint SIM has been unable to use T-Mobile Tuesdays. No one seems to have the resolution to this issue. Help would be greatly appreciated.