I have a company of mine where I sell custom computers. Doing really well, been going on for about three months now, with no problems. Sold to around 30 or so customers. Everyone was happy till this one guy comes around. So this guy orders my most expensive computer I sell, which cost $2000. So anyways he pays up front through paypal, and I build his computer, then ship it off. So anyways this guy claims he never got his computer. The thing is, FedEx says it arrived, and still he says he didn't get it. So now the guy wants me to refund his money. What should I do?