Complain and need answers

I hired car from them on November for almost a month but on the last day to return the car ,the taxi driver jump the car at back and was running out of time,my buss from mthatha departure time 13:15,i just tòok driver's details and promise to call hime so we discuss then,i took the car to the airport (mththa)report the accident and i had holding deposit of R12000 with them,to my suppress no communication from the car rental,until i call them to find out what will happen about the accident?the lady says she will escalate to the relevant department,i must wait for the email.after 12 days waiting for holding deposit and email for the quote,i had to hire the car from them again,then was told i am owing thrift and they took the R12000 to cover the damages but no invoices was send to me and i don't Belleville the bumper of that car can cost me R14600 ,i feel that they robed me ,i can't trust them anymore,i mean i have been using the soo many years,one more thing i phone to lodged complain with no help ,so i need my money and invoices of the damages,my number *** /***,email ***,id ***