I can't put in Medicare to advance my return

[MargaretL]

You don't have to put Medicare on your tax return.  It is not considered "Obamacare".  Form 1095-A is not issued if you have health coverage through programs such as Medicaid, Medicare or Children’s Health Insurance Program (CHIP).

When going through Health Insurance Tab in TurboTax, indicate that you had coverage (I'm assuming you had it all year) and Select No to Was anyone enrolled in any of these less common plans in 2016? (see pictures)