I Have a old T Mobile phone that i want to use with ATT. It is locked and i don't know how to get around it. when the tmobile sim is in the phone it just says unregistered on the phone. if i put my att sim card in it says contact service provider. i called tmobile and they wont unlock it and att says they cant do anything unless it gets unlocked. I need some help bad cause the phone i want to use was a real expensive one at the time and would hate to see this brand new nice phone go to waste. ive checked online bout unlocksim sites but not sure what to do and even if i pay how will i know if it will give me the right information. I need advise or a way to get this unlocked without breaking my back or my bank account