Just because you bought an iPhone doesn't mean that you bought it at the Apple Store more than likely you didn't, so you go to the place where you bought it ....It would be AT&T T-Mobile Sprint Verizon Etc. does that make sense? LOL
The Apple store can reprint a receipt
If you bought the iPhone in the Apple store They should of offer you a receipt. But you can always go to the Apple store and they can give you a receipt if you ask them for it.
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