Declining chronic medication

Our medical aid No: ********** 71 - Classic saver plan. I am on a chronic medication "Cymbalta" otherwise CymGen 60 which was previously covered by Discovery. We normally get the script from our GP which was declined by Discovery who then sent us to the original psychiatrist for a new script only to be told we are STILL NOT COVERED. Why? If you knew it was NOT COVERED by classic saver plan why send us to the psychiatrist to pay R1 700 then decline this again??? We pay over R6 000 per month for our medical aid and this is how we get treated. Complete waste of time, petrol and stress to my prejudice. Is this how Discovery treats paying customers by sending them from pillar to post knowing that you are wasting their time? Surely Discovery could inform us beforehand that the plan does not cover this medication? What are we actually paying for??? I am beyond furious and appalled.