That’s just bizarre. Have you tried emailing ebay?
Sounds like a glitch on their part – not sure how close to the end of the auction you were bidding, but it could have been a server lag that didn’t update your bid in time. Really I have no idea though. I’ve never heard of something like this happening. 🙁
Can you send a link to the auction and let me know which bidder you were? You can PM the info if you dont want it public. At what point did you bid 51.99 and did you receive a confirmation screen and a confirmation email afterwards?
I found the castle in question and there is a bid that is 2 sec before the winner and 4 sec before close but there are no auto bids after that bid. The only two possibilities I can think of are either the minimum bid was put in by mistake or there was a glitch.