MBSA./ GRAND CENTRAL MOTORS MIDRAND POOR CUSTOMER SERVICE

I bought a brand new c220 d from Grand central motors on the 30nApril 2018 To this date I have taken the vehicle back to the dealership 6 times for the refill on ad blu I started discussion with the dealership in July 2018 and the vehicle was left at the workshop only to find out that they have no solution to this problem I was also informed that thus is a factory fault I tried to get assistance from the customer care department but was told they are unable to assist and take up with a third party Since then I have sent them a legal letter which MBSA did not reply on the problem I also went to the ombudsman and there again MBSA did not reply They said they can only exchange the car if I can settle my car I did not invest in a popular brand to change my car in six months They want me to come up with170k with is not acceptable The only way they can help is if I trade the car in This is unacceptable I also asked them to exchange the car for the exact one I have with similar kilos but they are not willing to TAKE RESPONSIBILITY FOR A FAULTY VEHICLE PLEASE DONT A MERCEDES FROM GRAND CENTRAL. I NEED SOME HELP