Bad service polokwane branch

The customer service for polokwane brach is very bad.my sister bought a car and the car gave her problems same day. And she returned the car and she wanted to exchange the car and get a different one .the brach manager promised her that he will talk to head office. and she was also promised that she ll add up cash and get another car. It's been 4 weeks now and she still waiting for polokwane brach to call her about way forward. The brach manager there has been ignoring her calls. I can never recommend you guys to family or a friend .please assist my sister she can't keep on calling you guys because she is also losing money by making those calls.