HSA and Medicare

I turned 65 this month (April) I have made $500 a monthly contributions under the HSA family plan all along. I did not realize that I needed to stop contributions 6 months prior to Medicare kicking in.  My wife is 60 and still eligible for an HSA account. I already filed our 2020 taxes. Do I need to remove $3,000 ($1,500 paid in 2020, $1,500 paid in 2021) from the account by revising? Do I need to amend my taxes for 2020?