I'm not happy at all as a new buyer

I'm not happy at all bought a car from we buycars Johannesburg South 5 days back, yesterday when l was driving to church l was stopped by the cops and l gave them the permit that l was given from we buycars l was so alarmed when the traffic cop told me that the permit is invalid it doesn't even have a stamp to show which traffic department is it coming from and the car has got 2 registrations the one on the permit and the one on the lisence disc then they impounded the car, l called we buycars the only response l am getting is we are waiting for our legal team up until now the car is still at jmpd I'm really considering to open a case against we buycars because l can't pay for something that has been taken away from me