After you file

Never mind @OregonGuy  . I just saw your reply upthread where you mentioned having taken the "pay by check" approach. I took the same approach for want of a better option.

 

I had opted for electronic payment of the taxes due in the original 2020 return.

But on filing the amended return using the "pay by check" option for $0 dues, I got this following in the "returns accepted" email from turbotax.
This is very confusing, as my tax dues are supposed to be debited electronically from my bank per the original return e-filing I did.
 
Next step
 
All that's left to do now is mail your payment to the IRS along with your payment voucher (Form 1040-V).