Hi,
I have sold 6000 items on ebay, and sometimes items turn up weeks later, or are returned to me because the paypal address ( which is where i send them to) is incorrect as the buyer moved and never told paypal of the new address. I also have items go missing that have never been found. also, some are returned to me because the customer actually moved, then said " could you send the replacement to my mothers house, at this address etc" which I did, then, several weeks later, the original item is returned to me, unopened, with a note on it saying "moved, not known at this address" , so obviously a dodgy customer who moved then lied to me about his new address.
If you fill in a missing packet form with the royal mail, good luck. they are so complicated that , although my missing post comes to several hundred pounds, I gave up, as I filled in the form, sent if off, then they sent a reply back asking to see the receipts from the companies I had bought the goods from that I had sold the customer. ( I sell telecom/ broadband installation kits, which consist of several items bought from several suppliers)
This was a virtually impossible task, as I buy in bulk, and breaking down items into ones,value wise, was virtually impossible.
Hope you get it sorted,but, Always get proof of posting, you can then send that to the customer and let them sort it out.
Alf.