Hi i have purchased a used iphone 4 in INDIA when i used  my airtel simcard it says that use proper sim card, then i connected to itunesagain  it just says use proper simcard,  then i contacted my serivce provider Airtel they have informed that it is locked phone used in USA with AT&T service i need to contact then and get unlocked.

So now iam contacting u for unlocking my iphone 4 and also i have checked  the phone it only displayes 

please advice me how to unlock my iphone 4

Awaiting for your reply.

Thanks & Regards

D R

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