I was ****med by the dealership

i bought a car with this dealership on the 15 September and the cara has been showing me frames. I have been trying to get hold of them they all say i should call Joseph who is the owneer but when i call him he say he has network problems. They have tempered the KM of the car,the car was on accident they didnt tell me.the computer system,steering rack ,handbreak, radio almost everything is faulty on the car ,ooh i almost forget the spedometer is not working all this happens in less than one month. I will really appreaciate if i can get help