If you're willing to use a T-Mobile branded phone rather than your own phone, T-Mobile has wifi calling available.
Alternatively, if you can get any signal at all, anywhere in your house, you can get a signal booster; you can either buy one yourself from Cel-Fi, or T-Mobile will give you one with a two-year contract.
Alternatively, if you can get any signal at all, anywhere in your house, you can get a signal booster; you can either buy one yourself from Cel-Fi, or T-Mobile will give you one with a two-year contract.