hey guys, i'm a android person but got my gf a lumia 521 and she loved it. I ended up purchasing one of the "bring your own phone" sim card kits for t mobile prepaid since the guy i bought the phone off of didn't give me a sim card with it but when the sim card was inserted the phone displayed some error message about the sim card (unfortunately i wasn't there when she put the sim card in so i don't know exactly what it said ) and now the phone wont boot up past the nokia screen, it goes straight to a blank blue screen and nothing else. any ideas what happened or how i can fix this? thanks.