If your customer claims a Item Not Received and you sent your item via Royal Mail, UK only, you will need a claim form to complete and return before (and if) you are entitled to a refund from Royal Mail.
Claim forms are available from all Post Office branches or can be downloaded and printed off.
Alternately you can have one sent to you by calling Customer Service on 08457 740740.
Also here is the link to the Royal Mail website for the P58 form:
Royal Mail claims in formation and form
Please be aware 15 days must of passed before you can make a claim.
NOTE: I would highly recommend you refund your customer before this time.
Once you have carefully and fully filled in the form you can print off and send to:
When completed in full, the signed and dated claim form and all supporting evidence should be sent to:
Royal Mail Customer Services
PO Box 740
And good luck.
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