poor customer service

I bought a car on December 2019 at kia motors in alberton, I bought a 2017 used renult sandero stepway . two months later I started having problems with the car, lights started showing up, indicating that it is due for a service, on the same breath, the batterie died, and brakes stared screaming on me, then the front light leaking , it now has mist inside and I cant see properly at night,,i then went back to kia and spoke to the guy I bought the car from , I explained all the problems to him then he changed the battery for me and promised to also check on other the other problems I had with the car, then we went on a national lockdown meaning they were unable to help me , I recently went back to them with the same issues , and all of a sudden they don't want to help me claiming that it is my fault that the car has problems , claiming that I drove it for too long and that they don't cover brakes and lights ,, my question to the sales manager who didn't even know or understand their guarantee policy at the dealership was that how many months of guarantee does a customer enjoys from the dealership when buying a used car? he couldn't answer me, I then requested their guarantee policy in writing , he didn't have it, how can a sales manager be so clueless about such things ? how does he see that his customers are happy? the dealer principal didn't even want to see me, that how useless I am to them as a customer . I just want to understand this, I drove the car for less than two months and I started to experience problems , am I liable for paying for new brake pads and discs? and also the light? dealerships doesn't have guarantees on used cars? if they have a guarantee on used cars, how can I get them to replace those parts with the new ones? thanks phuti *** / ***