If the buyer wants a refund then they will have to open a return request within 30 days.
If they choose not as described you would have to accept or gain a defect n your account from ebay for refusing.
Once the request is closed you can appeal the decision if the item is not returned in the same condition but most cases go in a buyer favour.
Best add the buyer to your blocked bidder list here, https://www.ebay.co.uk/bmgt/BuyerBlock?
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