re: What in the hell is wrong with medical billing?

Had a medical procedure done a while back. Received statement from health insurance indicating they fully paid for it. A week later I received a huge bill from medical provider for same procedure. According to the bill, insurance didn't cover procedure. I called my insurance co. and was told the medical provider was incorrect, that the procedure was covered and they paid for procedure so I shouldn't be getting billed. Called medical provider and was told they'd look into it and get back with me, but they never did. Month later I received same bill. Called insurance again and was again told they paid for procedure, had a receipt of payment proving provider received full payment ( I was emailed a copy of this), and that I shouldn't be getting billed. I asked if they could contact medical provider and they said no. I called medical provider and they said the amount I was billed was what I owed, and insurance only partially covered the procedure. Called insurance again. They once again said that they fully covered the procedure but that the medical provider could charge me whatever they wanted to. I'm like wtf! Why have insurance if that's the case. Makes no sense at all. Whole thing is a scam.