My samsung galaxy core prime is kind of old. It has the same sim card in it. But recently I get locked out suddenly. Then the error code is on the lock screen saying sim is locked, there is no network and emergency calls only. I can get it unlocked by putting in my phones pku codes (which I had to wait on the phone for an hour just to talk to someone who knew what they were doing! Would a defective sim card make it lock like that?