What kind of lock? Phone lock, setup lock, SIM lock, AppleID lock? What company in U.S. Released phone? Verizon, AT&T, T-Mobile, Sprint? If it was a phone reported as list or stolen, there may not be much you can do.
Also install iTunes on a computer and connect the phone to the computer until it is detected by itunes. Try twice if not working.
I didn't try to change any settings because i can't even open settings. It stops on install and all. I' ve many times tried with itunes but it also didn't work