ReFILE 2020 Income Taxes

In 2020 I filed my income taxes using TurboTax Online Premier. I have my notice of assessment (NOA) and a NETFILE confirmation number. Now I need to make a small change and would like to use ReFILE, however, I cannot find the login page for the 2020 version of TurboTax, only 2021 and 2022. Any advice?