prepaid mobile shop llc / wireless mobile Sold stolen goods and overcharged my account new york New York

I was offered a deal to trade in my iPhone 6 to an iPhone 7 for $200 dollars as a special deal they also said they would add in a free phone cover too. On the receipt  the salesperson highlighted the $199.99 charge for the phone, and he told me about the 8% service charge so the final bill to pay would be $217. All other parts not highlighted on the bill would only be incurred if I were to use an AT&T sim in the next 180 days which I wouldn’t be as I was leaving the country.

I have now returned and not only is the phone blocked as it has prevoisly been reported stolen/lost  but I have been debited an extra $1200 (including $199.99 for a phone cover!!) I have also been charged $610 for a sim card they sold me for $15