Cant register my vehicle bought from them

I bought a chevy spark 1.2 ls that came from them its been a week im struggeling to get hold of the relevant person to assist me from their jhb and capetown office. I need to register the vehicle in my name the proxy at our traffic shows a mr BM van ZYL ID *** our traffic department did not accept the letter that was supp**** to me. I need a clear original letterhead with the proxy's details and also a business regestration certificate but im being sent from one person to another when i phone. I AM GATVOL!