Woodfords unjust overcharging and double charging

Rented a car from Woodford through rental cars with unlimited milage. On return of the vehicle I was sent a bill of R12000. They said I had 100kms a day free and charged me R5000 for extra kilometers. They also double charged me again for the rental I had already paid for through rental cars and added about R2000 on extra from what rentals cars charged. I phoned them and they said it was an error and they would amend it. I checked with them the next day and they said they loaded it on the system and the charges won't go through. Case closed I thought. A while later I saw on my credit card they still unjustly charged me the money they had no right to and added on another R3000 for a chip on the windscreen the size of a match head. After much phoning and many delays they refunded the extra kilometer money but said rental cars must refund me the daily rate (as they charged me 2k more). I told them 'no, I booked through rental cars, you unjustly charged me so refund' . After much arguing and being put on hold they eventually refunded me but still charged me R3000 for a stone chip the size of a match head. I don't believe they changed the windscreen but just put the money in their pocket and billed for a new windscreen. If I never checked the credit card and spent many hours wasted on the phone these charlatans would have unjustly charged me well close to R15000. They take money they have no right to and charge credit cards as if the card is theirs. Terrible company who should be closed down. I laid a complaint against them with the ombudsman but this is RSA and accountability doesn't exist in this country. And to add insult to injury they signed the car in in good order and then told me later there is a stone chip. I wonder how many other people banks balance Woodford has depleted without their knowledge