Vehicle broke down after two weeks of purchase.

I recently purchased a Mercedes Benz C220D two weeks ago, however i received the vehicle with an Engine light on that was never fixed. To my disappointment I drove the vehicle to KZN and was stuck on the road for hours with my family, I had to pay for the vehicle to be towed and they diagnosed that a faulty Alternator as it was no longer charging the battery. Multiple sensor misfunctions were coming on until the car was no longer starting. Mercedes Benz carried out a full diagnostic and picked up the issue with the Engine light as well the faulty Alternator and low brake pads starting to cause damage to the disc. We buy cars did not provide me with a Roadworthy certificate until today. The most frustrating issue was that I had to pay R7000 worth of towing to have the vehicle towed to my home as I got stuck in Bethlehem which was very far from home. I do have that kind of money however I had to pay as I stuck with my wife and small child. I am struggling to get ahold of the salesperson that was assisting me during the sale of the vehicle as i need this vehicle to be repaired. I have not yet paid my first instalment and this vehicle is already not mobile and is a Finacial burden on me. The warranty house has not received proof of payment hence i was unable to have the vehicle repaired. I have a vehicle that is no longer drivable and unable to claim for the repairs.