I got a message on eBay today saying " Hi, We need your help to unlock the phone we purchased from you in 2013. There was no problem until recently when I did a major OS update, and when I turned on the phone, the phone is in a locked state, and asking me to unlock by typing the password for an apple ID "x.....@gmail.com", which apparently isn't my ID." My question is I thought it was impossible for them to use a phone if someone else's find my iPhone was on for 3 years? I checked my apple account and there are no other phones on my account. I think this is this persons own account?