RMA versus DOL

Why did the DOL give away workman's compensation to RMA, they are unhelpful and do not even bother replying to you, whom are very expensive in comparison to the DOL. They even send you 2 invoices which I am question as to why. Last year they wanted to charge me an amount of R149,073.35 for less than 12 employers, what a story to get it reversed out and then still charge me interest for their mistake, I landed up paying over 21000.00 where as I normally pay between 6000 and 8000 by the DOL for more than 15 employees, this year they want me to pay more than 11000.00, just shows how the small businesses are being ********** and we must still put up with this till 2022. My question is why do they want me to pay 2 invoices?? And no one can explain to me how workman's compensation is actually worked out, why??