T-Mobile is now being sued for fraudulent charges. The same thing is happening here in Cannon Falls with our (Frontier) telephone service.
Ten years ago when we began telephone service, they automatically charged us for "hold" for second call, which we never had on our phone. This past year I discovered the charge and they would only refund for a year.
When service was on vacation hold for three months, after being reinstated, they automatically put us on long distance service which we didn't want or know we had. It was not used but billed for. I guess it really pays to check the small print since they are trying to "upgrade" our service whether we like it or not.
Let's hear from others if you find fraudulent charges when checking your bill.