Unfortunately unless you know the person you bought it from I think you’re stuffed. What platform did you buy it on? Shops like CEX will check these things before they buy them in, eBay might cover you using the buyer protection programme. If it was a private deal then you need to find the person you bought it from and ask for a refund but I doubt you’ll get much luck as the chances are they knew what they were selling and were glad to be rid of it for a sum of money.