Netcare incompetence

I was admitted into one of the Netcare hospitals in July 2018 and spent a week in the hospital. Upon arrival at the hospital I had to fill in my personal information as well as next of kin details which was done properly. To my knowledge, the Bill's were paid by my medical aid. However, 6 months later I get an SMS from Netcare stating that I owe them money. So I called them and queried. They could not answer any of my questions regarding why they waited 6 months to contact me and neither could they tell me what I owe them money for. But they demanded that I pay up. Now I've been handed over to the credit bureau due to their incompetence. It makes me wonder how much money has been ******ed from other people in a similar manner. I certainly would not recommend anyone using Netcare facilities due to this one issue. Other than that, the nursing staff, doctors and every other aspect is in order.