Cell plans/coverage issues


Senior Member
Not sure if this is a good place to ask but thought I would give it a shot.
A bit of background.  We live in an suburban area of somewhat low density - most people around us have at least an acre and 5 acres isn't too uncommon.  More dense areas are within a mile. We had ATT but decided to switch to Tmobile as it was a bit cheaper and they touted their network.  We aren't heavy users needing high speed - we just want something that works.
The coverage of ATT was pretty good here but if I was near my PC in the basement I had a bit of trouble with weak signals.  Not a real problem and easily worked around - just leave the cell on the other side of the room.  Once on a call it wouldn't drop no matter where I was.
Tmobile allowed us to do wifi calling, something that ATT didn't only because it was an unlocked phone not purchased from ATT but a model they also sell.  Crazy but that's what I was told.
Wifi calling works great when it works.  But apparently we need enough of a cell signal for the phone to switch to it.  I have gotten no provisioning messages several times at home and have to go outside to get a usable signal. 
I am a bit worried this is going to be an ongoing issue and maybe I should have stayed with what worked.
No idea if Tmobile supports home repeaters.
I do know that they have a cell connected unit they use for supplying wired/wireless internet to homes.  That's how they avoid having to lay cable or fiber.
The Tmobile online map shows weak signal where I am.
I've been using T-Mobile since AT&T spammed my grandfathered accounts (from the 1990's).  I purchased no contract T-Mobile SIMs after that.  They were unlimited in the beginning then they capped the internet accounts.  Recently they went back to unlimited in celebration of their merger and my long time use (?).  
As part of our unlimited upgrade, we want to say thank you for being a loyal T-Mobile or Sprint customer by upgrading your limited data plan to unlimited at no additional cost to you! Beginning April 18, 2021 most customers will automatically get unlimited high speed smartphone data at no additional cost on all current lines T-Mobile provided an in house T-Mobile repeater for me. (X2 homes).  It works OK.  One unit goes by a window and the other is inside of the home.
I have one SIM plugged in to a Yeacomm P21 CPE.  The CPE has an RJ-11 cable which works fine with a regular telephone.  I am using the CPE as a backup to the internet and a back up to phones.