I had on of these these yesterday claiming they had received the item in the last month that had not worked. I checked my history and their was no record of the buyer so I politely sent a message back saying sorry that I could not see that they had purchased the item from me withing the last 3 months. Haven't heard back yet.

check your sold history to make sure they haven't purchased off you then send a message saying similar. then leave it at that.