Oncology treatment account rejections (5th time)

My mother is undergoing Oncology treatment. We regularly reach a point whereby Momentum Health begins rejecting her oncology treatment accounts. I logged calls for this same problem in October 2019, February 2019, September 2018 and February 2018, so this is a sustained issue that has not been solved at root, causing me some dissatisfaction. There is some disparity between the treatment required and that which the Oncology benefit is set up, by the Medical aid, with for every treatment plan submitted. Please could an experienced agent review the account from 01 January 2020 and assess rejection of oncology treatments for Pathologists and the Oncologist. I need the email address of a specific person that I can send a list of the claim rejections to for reconsideration or explanation as to why rejection of the claim is acceptable.