Why can’t I make a amend to my tax return if I know exactly where I messed up?

[DoninGA]

An amended return, Form 1040-X, can only be printed and mailed to the IRS if the original tax return was not e-filed. The IRS will take up to 16 weeks or longer to process an amended tax return.

Before starting to amend the tax return, wait for the tax refund to be received or the taxes due to be paid and processed by the IRS.

The federal amended tax return, Form 1040-X, for tax year 2021 is estimated to be available in TurboTax on 03/17/2022

[xmasbaby0]

If you already e-filed you cannot change anything until the return has been fully processed.  The Form 1040X you need will not be available until mid-March.    Do not try to change anything on your tax return now or you will only mess it up more.