BP PETROL INTO A DIESEL CAR - DAMAGES CLAIMING

On the 16/10/2015,I stopped at BP Trio Cnr Kliprivier Dr &, Rivett-Carnett to fill up my car with diesel .The attendant filled the car with petrol. The following day after parking the car, I tried to start my car and had no success. We towed the car to the mechanic the Saturday morning, on the Monday morning I went back to the garage and reported this to the manager. After which he disputed and advised that the petrol fuel should not have been drained and the diesel should've been added to that than the car would be fine, he then concluded that there was something wrong with my diesel tank. After the damages was fixed on my expense, I took the invoice to the garage manager to reach a consensus in terms of damage and claiming for the damages due to the petrol in my diesel tank. He refused and disputed about payment stated that we can proceed with litigation and they will not be liable for the damages. The customer service provided by the management of BP Trio, is outrages and the fact that they do not want to take accountability for the mistake that they made is ridiculous. They will not own up to their mistakes, so this is how BP Trio is managed it's shameful to the franchise.