Discovery Medical Aid avoiding paying

I have been diagnosed with severe chronic sleep apnea. I did a sleep test at the hospital. I have been advised to immediately get a CPAP or APAP machine to sleep with every night. I did a trial with a borrowed machine from the sleep technicians and the results were fantastic. Discovery was approached and advised to assist me in getting a CPAP or APAP machine. They have refused and said they needed additional info and motivation. I went and got additional info and motivation from the referring doctor. I since have received no feedback from Discovery. When I called yesterday they advised me I have been declined again! I am tired of calling their call centre and trying to speak to a manager. Yesterday I was told a manager would call me back and explain the decision and yet I am still waiting again. Every time I call the call centre I have to explain from the beginning and it takes ages. I want to know why Discovery does not want to pay for this medical devise which would improve the quality of my life substantially as motivated to them by my Doctors..Very dissapointed I have been told the lesser known Medical Schemes pay for their clients without a struggle. Tome to move I think!