xbox onex

I have seen many posts related to issues with XBOX on the T-Mobile solution. The way T-Mobile does the CGNAT and the ports it is a problem. You might try using a VPN but that would probably add latency to the connections.

One thing you could try is the XBOX Ultimate Game Pass (cloud gaming). You can currently join for $1 for 3 months. It would be worth a shot. If you get good to excellent cellular speeds it would probably be a workable solution. You can try it and really have nothing to lose. 

https://support.xbox.com/en-US/help/games-apps/cloud-gaming/about-cloud-gaming

I took a look on Reddit.com and found some info but did not dig deep to see how successful others may have been. With the cloud gaming pass you could still put your XBOX gear to use. 

I no longer do much gaming on my XBOX but use it to stream videos so I am not an authority on this bad boy. Just offering a suggestion.

That is curious. It sounds like a problem with the Xbox itself. I assume you have tried to reset the Xbox and save games and data. I use a wired connection for my Xbox One for the simple fact that I don’t have to deal with the wireless network. The wired connection works very well for me. If a wired connection works then you can check for updates etc… and then trouble shoot the wireless network connection. It just sounds like a network issue with the Xbox to me. 

If you haven’t been here you should maybe start here: 

https://support.xbox.com/en-US/help/hardware-network/connect-network/xbox-one-network-connection