MPB item not paid!!!

I phoned to get pre-authoritation for my wive's annual MRI for a tumor on her pituitary gland (first diagnosed in May 2016). It was authorised and I was told to give the Xray department the correct ICD10 codes. Of which I did.

Yet after numerous emails and even my brokers involvement Discovery Health refuse to pay for the entire MRI even though my wife is entitled to 1 per annum as part of her Minimum Prescribed Benefit basket.

Please resolve this!