debit from account

hi we hired a car via our insurance from them for less than the 10 days the insurance had offered us - we barely used it as having been out of hospital was still in alot of pain . when returning it they checked it out and there was no damage and nothing mentioned about any damage many weeks later there is this large debit from my account - i went to the bank to find out who or what it was for and it was bidvest car rental of course surprised I contacted them and got a very flaky piece of paperwork besides the R450 admin fee there was this R2000 for body work - i have tried inquiring this to no avail .... the next time i need a vehicle i will rather get a taxi as it is hardly worth the added aggravation this has caused