promises promises bad service and and and

Sales person put a numberplate on vehicle knowing that it was incorrect. Plate fell off. Fine issued. Fine was handed to salesman in 2013 and he promised to sort it out. Now after more then 2 years a warrant of arrest was issued and i cannot take out my vehicles licence. He keeps on saying he is sorting out the problem but still nothing was done. As if this is not enough they have been costing me money from 2013. 1st selling me a tata double cab which could not be fixed so they settled the finance then selling me a kia sportage white vehicle which was in an accident and when the back door could not be fixed they settled the finance again. This means that twice they had to load shortfalls on to the next vehicle and this was done to the third aswell. So this also means that i was taken for a ride and done in with round about R20 000 to R30 000. What must i do? Now sitting with a vehicle and there is only one day left to take out the licence.