I sold my iphone on ebay. I sold it as unlocked and jailbroken. When I restored it to factory settings after it had been sold, it also upgraded to 5.1.1 which is not unlockable. I have cydia installed but now cannot unlock the phone. I'm not sure what to do at this point. Can the buyer still use the phone? Should I give it to him anyways and hope for the best? Or should I tell him upfront and not give him the phone? Any advice would be greatly appreciated.
Also, if anyone knows how to downgrade firmware 4.12.01 to an earlier firmware that IS unlock-able, that would be ideal. Thanks

Also, if anyone knows how to downgrade firmware 4.12.01 to an earlier firmware that IS unlock-able, that would be ideal. Thanks