Hey guys, I bought an iPhone 4S a few months ago off Craigslist and recently the home button stopped working. The phone's warranty is still in effect until 12/13/13 and I went to the Apple support site to start the service process. Apple then shipped me a box to put my phone in. When I took out my sim card, I discovered that the serial and imei on my sim tray do not match the ones on my phone. I checked the serial on the sim tray it points to a iPhone 4 with expired warranty. So what are my options at this point? Should I still send the phone in?