Cannot Reliably Connect Devices Home Internet

I just got T-Mobile Home Internet and while the speeds are great and very consistent, the internet service is not very robust.  I have the 5G Grey Cylindrical router.  If I try and connect Samsung TVs or my Directv box to the network, either by Wifi or wired ethernet, it often won't connect.  When the devices do connect they are unreliable.  Most streaming services won't work.  The connection to the router is fine, but the connection from the T-Mobile end to the internet often just hangs.  

The same is true on my PC or Tablets.  It all appears to work well but it's very prone to just hanging one process as if its trying to open a connection that will never open.  A good example of this is uploading videos to facebook, this almost always hangs.  It never begins the upload although other processes can use the internet fine at the same time.  It can USUALLY upload ok to Vimeo or Youtube but these also periodically just stall.  It's very flakey and unreliable internet.  This is with wired or wifi connections, and while one program is stuck trying to open a data connection, another program on the SAME PC at the SAME time can open a data connection.  

It makes the entire internet unuseable and frustrating.  While it generally works it's not reliable enough to play games etc.  You can be playing a game, or updating software, and all of a sudden that program will hang with 0 bytes going in or out.   But if you open the browser or start a different program that uses the internet, that new program can connect and download fine while the old one is still hung.

It's all inter-related.  The reason a lot of devices can't connect very reliably is because they are doing some sort of test that shows this internet is flakey.  Usually they will say something like the auto settings didn't work and to configure the network manually.  

It's very frustrating because my speeds and latency are fantastic, the connection to the T-Mobile network from the router never wavers it's always solid.  The connection via wifi never wavers its always solid.  But data ports from programs often just hang and won't open.

I still have Verizon Home Internet and I switch back and forth.  Verizon is MUCH slower but its reliable, I never have any issues like this with them.  Even right now.

Can anyone help?  Is there something that T-Mobile can do on their end to make data connections work more reliably.

The only thing that is really always reproduceable that demonstrates this is uploading video to Facebook, that pretty much never starts although once in every 20 or 30 tries it will start and when it does it works fine for that file.

-Roger Uzun

San Diego, CA