Can I get a plan with T-mobile if I do not have proof of purchase of a phone?

This is going to sound like I am lying, but please know that I am NOT….okay, my friend and I were working at a place that bought and repaired returned merchandise from different well known chain companies. We were told that if there was anything we wanted to feel free and take it if we wanted. Well, we both got mp3 players and our boss got a new office desk chair and my friend got a phone from T-Mobile…however, she has never got a plan with the phone because she doesn’t have proof of purchase obviously since she didn’t purchase it. Can she go ahead and get a plan with the phone or not??
I do have the sims card.

I don’t see why t-mobile would care wher you got your phone, but do you have a sim card? If you sign up with a 1 or 2 year contract you can get a FREE phone (with a sim card).

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