I have a medical insurance co. who agrees that they are obli

I have a medical insurance co. who agrees that they are obligated to pay for doctor visits 5 times per year but when the doctor bills them, they have not paid for over 18 months. Therefor my doctor's office makes us pay each time so the insurance is bogus. When questioned, the insurance company claims that their processing center is way behind and to be patient. I have called at least 4 times in the last 18 months and each time I get the same answer. So in essence, I am just throwing my monthly premium money away because they don't cover anything.