Damaged car

I rented a car with planet42 it started giving me problems within a week after I have collected it from the dealership. I reported this to planet 42. I requested to return the car and be given a better car but I'm not winning. I just want to change the car not to cancel the contract. But planet 42 is not finding solution for me they are taking me from Pilar to post. They are not accessible telephonically.

The auto response send through WhatsApp they don't adress my problem. Why are you not taking care of your customers?