Auction House Purchase Limits

I have suddenly found that I have a 24 car purchase limit on the Auction House on one of my profiles. I know that this is not standard because I just switched to a different profile and purchased 55 cars in 10 minutes on a different profile. I have emailed Forza twice now on the issue with no reply. I am one of the many that spends more time in the auction house than out racing so this is a real game breaker. Anyone else have this issue? Any idea what causes it? It would be nice if the game developers would communicate with the players in a more effective fashion rather than not at all. Thank you.