Buyer wants refund, made a claim, claiming the item smelling of smoke
I sold a coat to a buyer in the USA. The coat was delivered on the 2nd of November 2020 to the buyer. Since then and for 45 or 46 days I have not heard from the buyer and I did not receive any complaint at all. On the 47th day after contacting him and asking him for positive feedback, he finally replied to me and requested via eBay to return the coat and be refunded. He claimed that the cardigan/Coat smells cigarette smoke. I don't even smoke!! I am certain that he is just making up and has used the item for the last 45 to 47 days! I declined because he already has the coat for 45 or 46 days now!! I contacted eBay and it has closed the case in my favour! Now he has requested the refund via Paypal and has actually made this a claim. What can I do please? I believe his claims are false and that he is making this up having used my coat for the last 45 or more days. What should I do please?