Read the eBay help pages on Seller protection and eBay MBG( money back guarantee).

If the buyer opens an item not received case you should respond by adding tracking to the case ( even if you have already provided it on the original sale) within 3 days of the case being opened! eBay theoretically then covers the refund themselves. If you don't have proof of delivery (which you do!) then you would be required to refund them yourself.

Additionally, it’s to be hoped there is tracking; that, or an honest and happy buyer.

@letsbuytoday wrote:

I have sent an item to a purchaser which was left on their doorstep, as no one was home. I have a photo to prove that delivery was made. What happens from here?

Hopefully the buyer will take the item inside when they arrive home.

is buyer denying receipt?