How do I enter an additional payment on my 1040 which was made after extension and before filing?
For our personal 1040 return, I filed a 4868 extension and made a payment for the amount then owing. Soon afterward, I revised my draft return and determined that I should make an additional payment to avoid additional interest being charged. I made the additional payment using IRS Direct Pay.
(In Direct Pay, for the "reason" for payment, it did not offer a choice to mark it as a payment with the extension. That had been suggested on another post here, though it wouldn't seem to be correct as this payment was made after the extension. I chose "balance due" on the 1040.)
I don't see how to enter this additional payment in my 1040. It would appear to go correctly on 1040, Schedule 3, Part II, line 13z ("Other payments ... . List type and amount:"). Yet TTH&B won't allow me to enter it onto the form. Clicking the form takes me to the same line on 1040/1040SR Wks, but it doesn't allow me to enter anything there, either, though it does show a blue box which, when I've seen it elsewhere, I have been able to enter data).
