Bank Card USA Witholding of funds collected Westlake VIllage, California

In September, I contracted with Bank Card USA for the credit card processing for my business, which is a retail store.  Within one week trouble began when they put a hold on a transaction that was approximately $240.00.  After much frustrating conversation and many phone calls, they apologized and said that I was now OK for all transactions.  The money showed up in my account, and I was happy.  From then til now, most transactions have been in the fifteen to one hundred dollar range. 
  But on the 4th of November, I sold an item for $1700.00 and processed the transaction with the customers credit card.  When I signed up, I was told that all transactions would be deposited in two business days.  Friday arrived and no money was deposited.  On Monday I called them and was told that they had put a 180 day hold on the transaction because it exceeded $100.00.  No such limit was ever listed in the contract or was ever discussed with their agent when they signed me up.
  They now refuse to take any of my calls, leaving me to believe that I will never see my money.  Needless to say, I will not be processing credit cards through them again.