Hmm... in the cable world suggesting "roll the account" would purge the billing system / provisioning and setup the service again and it tended to work n resolving the issues. I'm not 100% on the billing system with TMO though but, having worked on the network side of the house and knowing the flow of the backend processes there's a disconnect somewhere in the binding between the SIM and metering system. The fact that things work when you add on data in the form of a pass seems to indicate the sim was provisioned for voice only for some reason.
This is why I suggested swapping the sim if all else failed w/o having to deal with support / store to resolve things. Sometimes it's out of our hands though to avoid dealing with a company to resolve issues. 99% of the time things just work but, there's always that seldom issue that happens to foul things up. If the sim swap doesn't fix it then have them cancel the line and redo it in the billing system.
It's oddities like this that made me port my number to google vs risking it not working or being lost due to a system issue. There are other online places to stash a number though. If you port the number out it will effectively cancel the line and allow for a new line to be setup. The new line shouldn't have issues and if it does then maybe pursue the legal option. It might cost you more than it's worth though but, I get the point of holding them accountable if there's not some clause that prevents you from pursuing things.
I'm about to switch to an esim in the next day or so though. My original plan was to switch to Tello but, Mint is rolling a $15 promo for all plans right now including the unlimited option. Of course with an OP11 not being on their supported esim list it's going to be interesting to see how it does/n't work. Odd thing is the QR from Target triggers esim to work for Mint sign up but, the app doesn't w/o out. Tello on the other hand gives the green light without any fuss. TMO app doesn't like the IMEI but, the website allows for esim as an option. Overall it's a mess unless you have Apple / Samsung / Google $1K+ devices it seems.