Shell South Africa one of your franchises damaged my car

I am extremely dissatisfied with the level of service provided by Shell South Africa. It says a lot about their company's image. I have filed a complaint with their head office regarding an incident that occurred at (Okgonne filling station at Garankuwa on 2nd of September 2023 11.55 am. where a petrol attendant poured petrol in my diesel car and now my car is damaged and no one wants to take responsibility for the damage to my car. I went to the station and spoke with the store manager, but he was unable to help me with the problem, so I took it to the head office, where I was told that I needed to work it out with the station. my question is when one the franchise gives a client a bad service shell south Africa that doesn't affect you ? my case reference is ***