Ebay Seller Dispute

I've been slightly preoccupied recently with a dispute between myself and an Ebay seller. I bought a special nail-file from them (for the Dowager) and, when the letter arrived the other day, the item was not inside. Everything else was there - the invoice and a light plastic case - but no file! I can only presume that the sharp end perforated the light, non-Jiffy envelope during transit and slipped out; because the entire package was sealed in a Royal Mail transparent bag with "sincere apologies".

I have sent four emails to the seller and they have not responded. They probably feel that it is the fault of Royal Mail. It's not so simple, though: Did the seller pack my file with due care?

I said earlier that this is trivial, at least in monetary terms with the amount involved being £4.95. The Ebay Community reckons that the seller should either replace the item or refund me; and the seller ought to claim from the Royal Mail.

If I do not hear from the seller today I shall begin the dispute resolution process, which means a phone-call to the seller and then Ebay.

Any feedback I give the seller depends on the outcome of the matter. The seller's feedback is 100% positive, which indicates that they are reasonably good; so this must be the first time this has occurred. They probably believe that the Royal Mail is to blame.