No commitment to Complaint Resolution

I have been given the run around for months now by the staff of the NedGroup Medical Aid scheme. I have sent through numerous emails regarding my query and all i get is a confirmation email that they are looking into the matter and nothing after that. The query is their response to their failure to settle the doctors bill for an emergency in hospital procedure that was done on my with me having a **** 100% hospital cover plan with them! I was told on the phone that the brochure clearly states that there is a tiered payment rate for multiple producers being done at the same time hence the shortfall in payment. That is **** and they just making excuses to pay, I went in for an emergency appendectomy in January, one procedure but they say the invoice details billing for each step which they think is multiple procedures. I think it is just an excuse not to pay but they wont confirm that in writing to me when I asked or provide any other feedback to date and i have the doctor hounding me for payment. This is in direct contravention of their responsibility to action complaints timeously and with consistant feedback. All i want is a response so that i can take this matter to the Ombud.