Every claim is a fight with Fedhealth

My contract states that I am entitled to a doctor's visit every year. I was ill and went to our local doctor. Now - once again - as happens every time- they refuse to pay me back. Reason - not a preferred supplier. The fact is that their preferred supplier is 130 km from where I live . Fact it would cost me more in travelling costs to see the doctor than the actual consult. This fight has been going on for 3 months now and I am so frustrated. They ignore my emails completely. I spent 40 minutes and all my airtime on the phone last week - with no result. I pay every month for 10 years very few claims - by the grace of God - but fight I have to every time for a legitimate claim.