If you somehow reported the Roth conversion on your 2019 tax return despite not having any 2019 Form 1099-R that reported the distribution from the traditional IRA, amend your 2019 tax return to remove that. Also make sure that your 2019 Form 8606 shows on lines 1 and 14 the nondeductible traditional IRA contribution that resulted from the recharacterization.
Report the Roth conversion that was performed in 2020 on your 2020 tax return where it belongs by entering the 2020 Form 1099-R that reports the distribution from the traditional IRA. Also make sure that line 2 of your 2020 Form 8606 shows the basis that carried forward from line 14 of your 2019 Form 8606. To reach the page that asks you to enter or confirm the basis that carried forward, click the Continue button on the page that lists the 1099-Rs that you've entered.
