EFT payment to 2019 Taxes in May 2021-Estimated Tax Payments Section Doesn't Allow Dates After 12/31/2020

Help-I made a payment towards my unfiled 2019 taxes in May of 2021 and the Estimated Tax Payments section of the online interview in TurboTax doesn't allow entry of payments made after 12/31/2020.  Where  can I enter that EFT payment to get credit now that I am filing my 2019s?