In 2021 I paid in to Pennsylvania ~6x the amount of income taxes due in 2020 in an attempt to meet the states Safe Harbor rules for estimated taxes. Despite paying in ~6x the amount of income taxes due in 2020 I still owe income tax in PA for 2021 which was expected but for some reason TurboTax is calculating an underpayment penalty and interest despite me paying in almost 600% of the prior year tax liability. I can't seem to figure out why that is or how to correct it or why the Safe Harbor rules are not applying here?
