refusing to refund my deposit

I hired a car from cape car rental on the 26of July for 5days, I paid R1500 and R230 per day CASH. Got an old faulty car ,then the next day I return the car and inform them about the problem but they refused to give me a good car. I return the care on the 5th day and I was told refund will be done in 14days ,till then we never received a call from Nikki up until I went to enquire they promise to pay via EFT. After a week I went back they say payment was made I ask for proof of payment and I saw that was not my account and the amount there was R445 not my R1500 . When I ask her about that she Lai in my face saying they receive the car empty while she knows very well that I went with her Son to the petrol station and fill up to full tank.then she said oohhh yes I forgot.Yesterday I went against We're I was told the lady who 's doing payment is in Pretoria and she can't be contacted her name is Lanie. I told Nikki since I paid her cash I expect to get my payment in cash she said she can't she has now access of the money. But she took my money to the bank. Secondly she promised to make a payment before the close of business, still nothing happened . The company is used to this not to refund people's money. Please assist me on this case...........021 ********** . They eat people's money.