desperate!!

I need help getting out an appeal letter to bc/bs of illinois, today I was denied. Don;t know why yet, have not talked to insurance company, the surgeons office told me something about not having a bmi of 40 or higher, she really did not know what she was talking about, all I know is that I was denied. I am disappointed. Do most people win their appeals? Does this mean I will not ever get this surgery with this company? My bmi is 35.5. I have a couple co morbs. thanks all