I freaked out about this yesterday, but it was an error on my part.   

Make sure youre not putting the 2020 Covid distribution in on the 8915E as a 2021 distribution....you only want to put the total at the top in the Smart Worksheet, then scroll down to either Line 12 (non IRA) or 26 (IRA) to input the 1/3 amount of payment, that should transfer the amount to the 8915F and make your taxable lines on the 1040 correct