Mercedes Benz Bad customer service

First, I would like to mention that I have always had a high regard for Mercedes Benz on the whole but after my experience will never consider this motor corporation or any of its vehicles. Secondly, I had purchased a high performance car (A45 AMG) a vehicle that is now in the possession of Mercedes Benz Constantia Kloof jhb for 2 months now. The vehicle status is still not resolved and a part (BOLT) is not in stock to complete the repair. This is frustrating as I am waiting for my vehicle for the past 2 months I have been waiting with no answers from both Mark in service department at Mercedes Benz Constantia and let me not even mention the *********** staff from Mercedes Benz South Africa (Themba and Sibusiso). I have dealt with Themba and Crm manager Sibusiso who has given me nothing but grief. Promises were made but never followed up. I was told by them of the status for the part will be updated again on the 17th of April. I have been hearing this since the 21st of February after my vehicle has been standing for 21 days with them already. They promise to get back to me but disregard me as a customer and have not contacted me since our last conversations which by the way the call was from me. I am tired of this ongoing bull****. I do not see the point of having personnel mentioned above if they are not able to assist. I have requested them on many occasions as per recorded phone calls to please have the manager or team leader or someone with a better understanding of this issue to contact me, to this day no communication. I'm going to resort to my legal aid and have this matter taken to court as I have lost on the purchase of this vehicle and I want to know how will I be recompensated for the loss on my warranty and motorplan? I want this matter to be dealt with, with in 48hours.