Whittaker-Axon purchased two items and paid for them within a few hours of the auctions ending, before I went online to send an invoice (which would have combined the postage). He didn't request combined postage, which most people do, and I ALWAYS combine postage when asked and when I send invoices.

Whittaker-Axon then left pointed feedback griping about the fact I do not combine postage.
I replied, stating he paid before receiving an invoice or requesting combined postage.
I even offered to send his next item out FREE of postage as a gesture of goodwill, as he has purchased previously and was likely to purchase again (I sell as a private individual within a small circle to fellow collectors)

I was therefore astounded to receive a rude reply, stating my response was dismissive and misleading and that he was going to open a dispute and would never buy from me again.

You cannot help some people. I wish I hadn't bothered to offer free postage next time around!