I bought a car at Ford Mccarthy

I bought a car at Ford Mccarthy. The car was coming up a huge smoke coming from the car. I switched off the ignition and went to investigate what might happen open the bornett as it was coming from it. I wait for the car to cool down. When I start the ignition it refuses to start it was dead. There were no suspicious signs on the deshboard showing that the car is not in good condition. I took the car with a tow truck to Ford Alberton. They are refusing to pay it they are claiming that I drove a car while it was overheating