How to figure out verizon wireless password?

Ok so I watched keeping up with the kardashians a while back and she used a phone service but it wasnt spoofcard cuz it didnt allow it but I did find out a service that takes me straight to his voicemail but it says please enter ur password how do i break it or trick it further because i wan't to make sure im right before I accuse him :-( its a verizon wireless phone please help thnks