Bonitas refuses to cover chronic medication

I am at my wit's end with Bonitas. My doctor prescribed new chronic medication which was refused by Bonitas, stating that there is cheaper medication which falls into the same category. My doctor stated pertinently that al the other options affected me adversely and affected the quality of life. After the second time my doctor requested authorisation, they still refused, but this time stating that "I do not qualify for the product." Two different reasons.

I phoned the chronic department this morning and after querying their actions, I was told to have the doctor send a motivation. Again. After he had done so twice.

I cant keep bothering the doctor with the same thing constantly.

Also, I pay a lot of money monthly just for medication I urgently require to be refused. The medication is expensive and I cannot afford to pay for them myself.