Account short paid , settled and then reversed

I am so disappointed with Discovery's chronic department such that I'm lost for words. I'm dialysis patient who needs treatment 3 x a week to assist my kidneys to function. On the 31 July during my usual treatment, I was notified by the clinic that my medical aid is suddenly not paying in full and I'm now responsible for a bill worth over R20 000.00 . Puzzled I asked for phone to contact medical aid on a call that lasted for 3 hours. I was told the reason was the doctor giving treatment was not registered on network so they should register in order for payment to made in full. The clinic brought to Discovery's attention that there are other patients with same option and same doctor BUT their accounts are paid in full and uptown date. Discovery then reviewed the matter and Eben called the clinic to inform that they've settled account and rectified error. Today the payment was reversed and Eden told the clinic to tell me that I must seek treatment elsewhere. This is very disturbing to me because I've been receiving treatment in this clinic for over 2 years and suddenly I must seek treatment elsewhere because it's not on prescribed minimum benefits. How can discovery agree to treatmen