Treatment for Life threatening Condition DECLINED

I was diagnosed with a life-threatening condition. In the words of my neurosurgen, I'm "sitting on a fatal time bomb". He recommended emergency treatment. After sending all the necessary documentation through, I have just found out that Discovery has declined treatment for my condition. Their reason "according to our plan guidelines, it's not an emergency". So basically I only have access to the treatment after I have a stroke. I have been on the phone for two weeks trying to upgrade my plan. Each time I've spoken to an agent they've sent me back to the doctor for more information and applications to fill out. I now only have 2 days left to upgrade. After sending motivation letters, the treatment plan, their PMB application, procedure codes and ICD10 codes, they still refuse to give me any information as to which plan will cover the treatment I need. I have tried to explain the gravity of my situation to Discovery, but it seems that they have taken a firm stance, disregarding an experts opinion in refusing the prescribed treatment. I have been making contributions to this company for the last 20 years, and on the occasion that I require emergency treatment, they've turned their back without concern. It seems this medical aid is all business, and no heart. Super clinical in its approach. I'm shocked, but have no alternative but to continue fighting in the hopes that someone listens.