My Medicare Part D plan denied coverage of my drug. How do I find out why I was denied coverage?

What if my Medicare Part D plan determined that my drug was not medically necessary?

What if my drug is not on my Medicare Part D plan's formulary?

What if I can't get my drug because my doctor did not obtain prior authorization from my Medicare Part D plan?

What if my doctor prescribed a dosage that is not covered by my Medicare Part D plan?

What if my doctor prescribed a form (liquid versus pill), or type (generic versus brand) of drug, that is not covered by my Medicare Part D plan?