I paid someone to unlock my samsung that was with AT&T. He said he unlocked it but there is a separate lock on it. He said there was a SIM lock. Did I get duped or is it true that there can be two separate locks on the phone?
Indeed. The individual you paid unlocked the PUK code, which is for the phone itself. But like Maziar mentioned, some company's have SIM card locks on their cards, which in that case, you may have to try and see if ATT or whatever carrier you want to switch to will give you the code.