I bought an iPhone 3G on eBay that was supposedly unlocked. After I got it, I put in my sim card, made a call with it, and since it all seemed hunky-dory, I took the card back out, and waited two weeks until Christmas to give it to my daughter as a present. Then, since it had been a couple weeks, I plugged it into my Mac to recharge the battery, put in her sim card, and now the phone just keeps searching and searching looking for a signal. (Also when I try to import the contacts from the sim card, it blinks for a second, but doesn't import.) I also took the sim card out of my son's phone and tried that in the phone. It had the same problems (searching for a signal, couldn't import contacts). By attaching the phone to the Mac, did I somehow re-lock the phone? The phone has Cydia installed, not that I know what that does, other than imply it was jailbroken. I brought it to the T-Mobile store (that's my carrier), but the guy there wasn't too familiar with iphones and couldn't help, and I brought it to the apple store, and they couldn't help because they said it's been jailbroken. What do I do?