It's not possible for any here except the OP to know the details of this transaction, however, I have been on eBay for a LONG time and have had 577 transactions, all as a buyer. Over the years, I have had only a handful of transactions that went wonky....until recently.
I saw a small pair of Polk speakers in a 'No Reserve' deal for $74.99 with free shipping so I went for it. I ended up being the only bidder, so I won. About an hour later, I got a notice that the deal was cancelled. When I looked at the reason for cancellation, it said "Buyer Cancelled".
I then sent a message to the seller explaining that I hadn't cancelled but, unsurprisingly received no response. Since the deal initially went through, I was able to leave feedback in which I gave the seller a negative and explained my reason. The next day, my feedback had disappeared along with any record of the transaction.
I then looked at the seller's 'Items for Sale' and there were the speakers with a starting price of $79.99 and a shipping cost of over $40. OK, I get it; he goofed and forgot to charge shipping.
I did a search on this and there are a whole bunch of buyers who are complaining about being falsely accused of cancelling an order. Ultimately, I didn't lose anything on the transaction, but it seems like a pretty tacky thing to do on the seller's part. Incidentally, the purchase price was not reimbursed for almost a week.