Your estimated tax payments are credited on the day the IRS receives them.
If you are late (as you stated) there can be a penalty.
The next and last ES payment is due 1/15/2022.
you can make that payment today with 4x the quarterly amount, if you desire.
OR
just 1x the quarterly amount.
NOTE: don't send ES payments if your withholding is otherwise enough to cover your tax.
