Overcharged by 3 times the amount and error not rectified

I was charged a deposit of R1267 in January for a 1 day car hire which was refunded to me in Feb. I recieved an invoice for R657 but was charged R1934 on my credit card. I have reported this to first car rental and await a response. I am deeply disappointed was I told that the R1934 included the deposit only yo find that I was infact charged R1934 with no explanation as to why the additional R1200. I was deeply disappointed at the waiting period to recieve the car now to fund I have been overcharged, how can a 1 day rental cost R1934??? I await an urgent response from the company to see how this will be rectified. I find this extremely dissipating and highly unlikely to ever use this company ever again. I advise all clients to ensure that charges are thoroughly checked as it looks like they **** people and add 3 times the actual amount.