Hyundai south Africa Hyundai Benoni

I bought my second car at Hyundai Benoni last year but last month was supposed to renew my disc I was told the car need to go for roadworthy and I will have to pay for it. I'm surprised it never happened with my first car at the same dealership. I'm very irate because I'm driving around with expired disc also outstanding fine on the disc that does not belong to me. Please help a.s..ap