I'm on AT&T, my girlfriend on Verizon, and the amount of areas where she can get coverage and I can't are large -- we had an hour and a half car ride recently w

I'm on AT&T, my girlfriend on Verizon, and the amount of areas where she can get coverage and I can't are large -- we had an hour and a half car ride recently where she had signal the whole way and I had no signal at all. Meanwhile, T-Mobile won't even let me activate a device with my phone number because they don't support this area.