I sold an item royal mail says delivered and pic buyer says yes that's my door but I haven't received it. Now they want refund of me how do I stand as it proves it was but they say not thanks for any help
So long as your tracking has been entered on ebay and shows as delivered, you do not need to do anything. Any bad feedback left by buyer can be appealed.
Buyer could try his payment provider, but again proof of delivery should settle any chargeback.