Bidvest warranty

I have a mechanical warranty with Bidvest for more than two years. My vehicle went for a service yesterday and the service provider discovered some faulty parts and I told them to call Bidvest because my car is covered. Only to be told that they don't cover those parts and only approved a R1000 which I could pay myself. These people cover parts that hardly give problems and not the major parts. I am looking for another service provider not this useless company.