Total over the lack of service delivery from Discovery and FNB

I am still not satisfied with Discoveries answers. How can they say you are billed for the previous month. So I join a medical aid, I only pay month end. No medical scheme in there right mind would do this, you pay for the 1st of the month and then are able to have benefits. I need answers I have spoken to so many people the story always changes. FNB who Discovery said I must contact as Premium came off but Discovery didn't receive it. I got one call from FNB and I was in with a Dr. and asked them to call back to date nobody has called back. Is this the service we are now getting in SA.