I Prefer Symbricort 160/4.5 Over Advair 250/50. However, My Insurance

I prefer symbricort 160/4.5 over Advair 250/50. However, my insurance coverage won't pay, only on Advair.
My doctor is willing to switch, what do I have to do to over ride my insurance, telling me what medication I can and can't take??
I pay them a montly payment, I feel I have the right to choose what meds are best for me, not the.
My supplement plan is w/First Health and I "hate their company and policies".