i bought the iphone about a week. and i did everything in one of the post on how to unlock it. it says it's unlock, i get no sim-error/youtube works fine and all the other nice stuff that comes with it. but i don't get services, i have inserted tmobil sims card and i get no services. i also install my sister att sim card on my iphone and till no service. and her sim card is the original that came with her iphone and she has a accound with them.. can someone help me plz...

Did you lockdown after unlocking?

no i don't think i did that, how do i that lockdown step..