Poor service from Fedhealth medical

I am very disappointed with Fedhealth medical. After paying them a hefty premium each and every month for many years I have had hospital codes for an upcoming shoulder operation unnecessarily declined, advising me that I would have to cover these codes at my own cost. My specialist surgeon has written letters motivating these codes should be covered as they are critical for my operation and are not duplicated codes. Fedhealth does nothing to assist, does not provide specific reaons for declining and simply declines the codes despite my requests to escalate the matter. This is completely unacceptable and unfair as I have comprehensive hospital cover.