Unknown contacts and photos appearing in my new iphone?

I just bought a 5s on amazon. The phone came in new, sealed, and obviously no signs of use. When I turned the phone on and insert the sim card, it only asked me to setup the Wi-Fi and activated the phone. Then I found lots of preinstalled apps, a bunch of unknown contacts, and lots of pictures (most of them were from 2015!). What the funk happened? I'm an android guy and ios is new to me… Please help!

Apparently it wasn't a new phone you got on amazon

You git a nicely repackaged phone in shrink wrap (easy to do with a shrink wrap and a hair dryer). Contact the seller for a refund or exchange.

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