help get at&t unlock cell phone

[Android Question]

i brought at&t avail z990 cell phone from friend sold to me and am very frustrate on get at&t unlock
.. i put my tmobile sim card in that not operate use pls,. help me
my email is maidenmat@aol.com

 

[Rukbat]

Go to an AT&T store with your friend AND his bill that shows that either his account with AT&T is closed or that he has no current balance. Ask if they can call and get the unlock code for you.

If not (if there's more than 1 AT&T store in town, try another one), you can find companies on eBay that sell unlock codes. You supply them with the IMEI of the phone (each individual phone has a different code) and, for a few dollars, they'll sell you the unlock code for that phone.