Auction House - can't get items back

[Kwal]

I noticed how the previous topic about this was locked, but what's stated in there by Logics doesn't work for me. I put up 2 small ponies for sale for 3500 gold and then realized this was a mistake since you can't split them (which would  be a pretty good feature by the way - being able to sell only one of your items of a certain type, I'd have put it up in Feature Request but there were already 5+ suggestions made today).

Anyway I press purchase on them and I get the message You do not have enough gold to make that purchase. What's the deal here?