You need to get the original owner to call ATT and unlock the phone. When they call, ATT will unlock the phone immediately as long as they can prove that they were the original owner. I think they may ask for billing address, last four of SSN, etc.
"usually i just go out sober, find the drunkest girl at the party, take her home, rail her, then once she is good and passed out i then paint peanut butter all over her, call my dog in, she licks her, i watch and laugh, then at about 5am i carry her outside to my bush, drop her in it, put on a mask, and pour cold water all over her face. She usually wakes up and one of two things happens, she screams and stumbles away, or she doesn't wake, in which case I fuck her again." - ECB