for the months you have medicare you can't have an HSA contribution. an HSA can not be used to pay insurance premiums. that includes Medicare, B, C, and D. there is an exception for specialized insurance like dental, vision cancer coverage. any HSA distributions used to pay non-qualifying expenses is subject to a penalty. any excess HSA contributions not withdrawn by 4/15/2021 are subject to penalties.
you need to read IRS PUB 969
https://www.irs.gov/forms-pubs/about-publication-969
if you don't understand it, you need to upgrade TT to talk to a pro or use and outside professional.
