No. It is an illegal insurance practice for an agent to sell you a Medicare Supplement or Medigap policy if the agent knows that you are already enrolled in a Medicare Advantage plan -
unless your Medicare Advantage plan coverage ends before the effective date of the Medicare Supplement.
Remember that you will use either a Medicare Advantage plan - or you will use your Original Medicare A and B plus your Medicare Supplement. But these the two types of Medicare coverage
are not the same and do not work together to bring you
more benefits.
See the related question:
"Can I join a Medicare Advantage plan if I already have a Medicare Supplement?"
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