Ridiculous service

I bought a used Audi A5 from Mazda bruma being assisted by David Mahloko, after 4 days the car started jagging, I then took it back to them, after 9 days of stories and lies I went to both Mazda and Audi to follow up only then did Jean-Marie (used cars sales manager) intervened which did not make much of a difference, the car has been sitting at Audi bruma for the past 14 days, I still have to follow these two dealerships around while being sent from pillar to post almost daily, there's no commu ication whatsoever from them unless I contact them