@rfsajohnson Medicare is your PRIMARY payer, Medigap is secondary. Your Medigap plan does not adjudicate claims, they only pay what MEDICARE tells them to.
You did not elaborate on what was not paid, nor the reason for the denial.
If your provider properly coded and documented the claim there is no reason for Medicare to deny a MEDICALLY NECESSARY claim.
So far there is no "fine print". This is all spelled out in the Medicare and You Handbook 2022, pgs 75 - 79
https://www.medicare.gov/Pubs/pdf/10050-medicare-and-you.pdf
If your provider billed you for a service that Medicare would not normally cover they should have presented an ABN form BEFORE ordering the test or procedure
https://www.medicare.gov/claims-appeals/your-medicare-rights/advance-beneficiary-notice-of-noncovera...
Absent the ABN form you are not obligated to pay for services your provider SHOULD HAVE KNOWN that may not be covered.
To learn why Medicare denied your medical claim, login to your MyMedicare account and review submitted claims. Any submitted claim that is denied will include an explanation as to why Medicare did not pay the claim.
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