Are you sure you auction them? Did you auction them at the same time or one by one? Check your current coins and try to remember how much you have before you auction the trophies.
The reason why I am asking this is because some people mistakenly selling their items instead of posting them in auction. If you go into the sell items panel, the "SELL" and "POST" button are adjacent to each other and if you become careless, there is a chance you hit "SELL" rather than "POST".
The only way to know if you SELL them rather than you auction them is to account your coins. GOLD TROPHY sells only for 100 coins, so if you are losing 9 trophies and you got additional 900 coins which you cannot account then you probably sold them rather than auction them.
If you are sure that you auction them and they are missing, just report an incident at http://help.ea.com having a screenshot of whatsoever related to the incident helps.
