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Check the email confirmation from Apple for the iPhone's purchase. It's essentially a 100% certainty it states a signature is required upon delivery. Meaning, they can't just drop the box and go. They have to take it back to the truck and try again the next day.
That is the main point.
At this time of year in particular, drivers are overworked, and the yearly temps don't always follow the rules. We replaced my wife's old iPhone 5 with an iPhone Xr. The email stated that yes, a signature was required. And yet, when the driver dropped off the box, all they did was ring the doorbell and leave as quickly as possible. I work out of the home, and from the time the doorbell rang and I got to the front door (all of 15-20 seconds), the driver was already back in their vehicle and pulling away.
The point being, no signature was ever given by you for reception of the item.
- Check the email, and/or call Apple to confirm a signature was required. I'd be very surprised if it wasn't.
- Call UPS, FedEx, or whoever was responsible for the delivery who signed for it?
- If no one signed, then they are responsible for reimbursing you for the stolen item.
- If it was signed, then it was fraud. You should be able to prove it wasn't you by the time stamp of when it was delivered. As in, you weren't even there because you were at work. And again, the delivery service is responsible for reimbursing your loss.