Refusal to Reimburse for Services Rendered

I submitted a claim to be reimbursed for consulting Dr Shabeer Jeeva, a psychiatrist from my medical aid scheme administered by Discovery, LA Health. To my surprise, I am told that they do not pay for services rendered by this Specialist. When I asked for reason I am told that their decision and I must ask the service provider himself. I have spent R3080 with the understanding that I will be reimbursed amount as per the scheme. But dololo! Do medical aids prescribe service providers one must consult or not consult? If a scheme is having a problem with a particular provider, why should a member be penalized for consulting with him/her? I feel my freedom of choice is being tempered with. I believe problems between service providers and medical aid scheme should not involve a member! Please help, as I do I understand why should I suffer while having a medical aid.