DFU restore = iphone still unlocked

[BarcaMagic]

I have to take my unlocked with tmobile 1st generation iphone to apple store for service , or even better replacement.I put it in DFU mode and did a restore in itunes when it was done i poped my tmobile sim card back in and its still unlocked .How can i relock it so they wont know it was unlocked.

Its 1st generation and im on 2.2 im not sure what modem firmware since its on connect to itunes screen .
Any help will be appreciated.

[StealthBravo]

Every time I restore it relocks it. That is weird. You can try it again but I don't think they are going to pop a tmobile sim in it to check it out. They usually will do a visual check of it to look for signs of jailbreaking, like themes and such.

[BarcaMagic]

Well im guessing they wont check it with tmobile sim , but since its still unlocked im sure their program will show active unlock .

Thanks for your help ill try restoring it again.

[StealthBravo]

Did you update your baseband? Are you bootneutering?

[BarcaMagic]

I honestly have no idea , i used winpwn to unlock

[StealthBravo]

If you updated the baseband I would think that would relock it for sure. I dont know much about winpwn, I'm on a mac