Lack of proper communication and practices

Good day I would like to bring to attention the lack of service and communication from Bonitas. I was on Bonitas medical aid as a company benefit.After a year the company that i was employed by was not performing as well as expected and decided to retrench staff,unfortunately for me i was one that was retrenched and was asked to leave the same day with a one month paid notice. They advised me that i will be covered until the end of the month on the medical aid and then they will cancel/terminate it as it will no longer being employed. The company paid the benefit in full every month for this medical aid so myself and staff was not responsible for any payments.So time had past after being retrenched which is now 2 years and i get an email stating that i have been handed to a company called CreditWorx for an out standing bill that was not paid by the medical aid.To my amazement i receive this 2 years later when i was not responsible for the medical aid payments.I was retrenched and the medical aid was a company benefit so why am i liable for the bill that was not told to me about as when i left the company told me that i am covered for that month and then will be cancelled so any outstanding bills was supposed to be paid by my company not me. I am not even sure why the outstanding bill was not sent to me earlier but 2 years later.This is seriously not on because how can you send someone a notification 2 years later and say that i have been handed over after just 1 notification. Some one needs to take this up as this is not correct to be treated this way after 2 years to be sent a notification that you have been handed over with no previous correspondence and be liable for a bill that i am not responsible for.I will not being paying this. Bonitas needs to contact the company i worked for with regards to the payment as i still had savings and funds available.