so, this is my situation: i purchased a go phone package, and i had an iPhone i wasn't using as a phone, but as an iPod. it was a 3gs iOS 5.0.1 jailbroken device. then i purchased this go phone package in an AT&T store. the woman activated the sim card with the crapy phone they sell with the package. then i yanked the sim out the phone and stuck it in the iPhone. nothing, something like :INVALID SIM. then i restored the iPhone, and upgraded, cause i have previously installed some apps and changed a lot of settings that wouldn't allow me to use a sim card. thats what i thought. the iPhone looked like new. it asked me for a sim card, i used this one and iPhone was activated correctly. and now comes the problem, it says NO SERVICE, despite the iPhone was activated, and even recognize the sim card. don't know what to do, please if someone does, could let me know? appreciate it