I got my dad the iPhone for Christmas. I activated a prepaid number on T-Mobile, then ported it out to Cricket Wireless so I could take advantage of their $100 port-in credit. I was helping him block some numbers (people calling looking for the previous number's owner) and I noticed something fishy. 3 Missed FaceTime calls that said "FaceTime answered on other device." My dad only has his 1 iPhone and no other devices. No other devices using his Apple ID either. This leads me to believe that the person who had the number before still has FaceTime activated to this number. I pray they don't have his iMessage too.