Discovery let me down when I needed them the most. 1st time used in 16 years

Iv had Discovery since 2007 (16 years). I have never used the hospital benefits until now. Iv been diagnosed with a serious Chronic condition listed under Discovery Chronic. Discovery intitally refused to pay for a scan. They then approved the MRI scan as per authorization code ***7. On this basis I went for the scan since i could not afford the high amount. 1 week later Im now told that Discovery has rejected the MRI costs. Im now left to fit a bill for R15,0000 which I never budgeted for. Why approve and then reject? Discovery is a **** and all these years took my money. When I needed them, they completely let me down. Do not be fooled my Discovery medical aid. Hope the NHI kicks in soon so healthcare is avaialble to all. These corporate clowns must learn a lesson