Discovery cares for themselves not patients

Dear people out there. My mother was diagnosed with breast cancer earlier in the year. The oncologist registered her for the oncology benefit as a chronic patient. I was contacted by discovery before the treatment to say that everything related to her treatment will be covered. Now we are getting calls to say some treatments are not covered and that some of the blood test is not covered. My mother is a old lady who doesnt work and cannot afford additional expenses. Thats why we took out a medical aid for her. In today's economy is this how you treat loyal customers in need of medical care. After losing your hair, having skin issues, nails falling out and loss of weight,sleep and strength on top of that you add stress by doing the opposite of what you informed us.