I have a jailbroken iphone 3Gs. I do not want it jailbroken, so I requested an unlock from AT&T and they granted my request. But when I tried the unlock that first updated my phone to iOS 6.1.3 or 6.1.5 (I can't remember what the latest update is), it didn't work . I never got the message, "Congratulations, your phone is now unlocked." Apparently, I was supposed to reset it first, but I found that out too late. Now it is stuck at activation mode and will not read any SIM card I put in it . I even took it to an AT&T store where they put one of their SIM cards in it from a display phone that supposedly had a contract on it. I have tried DFU mode and restoring it over and over again, but to no avail. I read that you can use redsn0w to fix the problem, but I am worried about putting iPad Baseband on the phone since I do not have the serial number and do not know what year it was made in . Is there any chance the Apple Store will unblock it? Can anyone help me to resolve the problem? I am not very tech savvy. So I may need pretty detailed instructions. Thanks in advance.