I recently purchased an iPhone 5 from a seller on Craigslist. Luckily I had an old sim around house and I was able to call AT&T Wednesday night to get it activated. Fast forward to today, my visual voicemail is not working at all. I contact AT&T support for assistance and I'm told based on the IMEI that my i5 is coming up in their system as an unknown GSM phone and I can't use visual voicemail. The rep told me she would submit a request to have it added to their system and that it can take up to 2 weeks. This has never happened with any iPhone I've used and it just seems odd. Has this happened to anyone else?