Poor service hiding problems of the car

I bought a car on the 11th of December and the cars is giving me problmes of starting since i bought it i even bought a new battry thinking its can be one,yet its gaves me problems i called the consultant lady as she was exited to help me buy a car and i even recommended her on social media and here,coming to my surprise she changed shes a different peraon now who cnt help me and teling me that i can not be assistant,i was not made aware of the starting problmes hence i got a copy of the car problems ,if i was told i wouldn't spend 76400 for a car that das not start,i dont have a month with the car but i cnt be helped ,how can i be assistant on this?