If a new Vodafone account has been created, with an iPhone sent out, in your name, and you know nothing about it, I can’t think of a single explanation for that that doesn’t involve identity theft.
How it’s ended up with you might have a few reasons – they tried to get it sent elsewhere but the provider reverted to delivering to the billing address on a new account, or a “test” purchase to see if those details were right / sufficient to pass checks / ensuring you’ve got good enough credit (before moving onto something “bigger” like a car, a personal loan or even a property scam), but that isn’t important – what is important is that someone other than you knows enough about you to be able to navigate from “Hi, my name’s scholarsgate” to “here’s your expensive new contract iPhone Mr scholarsgate” and you should be very worried about this.