Deposit R4000.00 Disappeared !

Is there an ombudsman or regulatory body that regulates the car rental companies? I hired vehicle 7th july and returned same day. Deposit of 4000.00 taken from my account. Today is the 23th of july and my deposit has disappeared. I made over 20 calls before i was contacted my Nicola the manageress from port elizabeth airport. She emailed me proof of payment and says money has left her account. I have not received it in my account. I have been to my bank thrice and they cannot help. Nicola says money is paid out and there is not much she can do. She expressed her frustration that she must sort out someones elses mistake asmoney was not supposed to be banked out,suppose to be holding deposit. She cannot help. The number for deposit queries is never answered at head office. The numbers for the pe depot and airport are out of order. My sincere advice to anyone who wishes to rent from dollar is... PLEASE DO NOT RENT FROM THEM. If anyone can help me on what i can to recover my deposit,i would appreciate it.