2 YEARS of NO problem solving skills

We have been struggling with our vehicle for 2 YEARS NOW at Volkswagen Middelburg Mpu. Parts that are installed are faulty Volkswagen parts and keep on failing. The part has been replaced 3 times already. We have spent close to R50 000 and still receive a vehicle which is faulty. This is unbelievable and unacceptable. All effort we receive from the manager is a "we will have to check again". This is really a disgrace towards Volkswagen