Your heart drops the moment you open that envelope or portal message and see it: your medical bill denied by insurance. You thought you were covered, you went to the doctor, maybe even the hospital, and now you are staring at a number that makes your chest tighten. The bigger question hits right after the shock settles in. You are not alone in this frustration. Research published in JAMA shows that about one in five insured adults still gets an unexpected medical bill, even w