Audi South Africa Arcadia damaged our Audi A4

We took our fully paid cash A4 Audi car for service for an annual oil change and brake pads to be replaced at Audi Arcadia Pretoria, however within a week our new car was leaking oil and it switched off the engine since, they damaged our car. We took it back to them, but even to this day they haven't responded to us, we demand a new car or our money back that we used to buy our A4 audi car.