Sold a defect bakkie (not test drived )

I bought a car Mazda 2009 BT50 NSC10534 diesel auto in Petermaritzburg. I live in Gauteng and I travelled to go fetch it. I then bought it cash(No test drive was done) and on my way back the car started overheating after 250km of driving. I the checked and found that it mixed oil and water and the turbo is failing and making it to smoke too much. I asked for a towing truck and tow it 370km to jhb at my residence. The following day I phoned the sales guy and told him I got stuck and he said he will give his Manager's number but he did not. It's been three weeks calling the Webuycars call centre number and was told to take the car to any RMI approved workshop of wich I did and the car quotation was over 50k and I'm told Moluleki will call me back and he hasn't bothered to call. My reference number is 136969. My alluminium Bussiness is stuck because I have a useless bakkie parked