Extremely Bad service

At about 17:30 on Sunday 05/07/2015 one of the petrol attendants Siya at BP in Diepkloof Zone3 poured Petrol in my car after being requested to pour Diesel. They had to drain it out and after they had done that the car wouldn't switch on at all. I spoke to the supervisor who had gone home and left the situation as is and asked if they will arrange for me to get home and she had to call the manager who was also not in on that night and call me back after speaking to him/her. After calling my insurance, they recommended to move the car to a safe place so they sent a tow truck at about 00:00 midnight they towed the car and also took me home after waiting for feedback from the supervisor who apparently \did call back and organised for me to get home"Now they are claiming the car was already broken when it got there and are refusing to pay as they say its not related to contamination and also refused to pay for towing the car as I was instructed by a person who was not even at the premises to live my car there overnight unattended. You guys messed up my car and I demand to have it in the same state as it was. I did not push it there"