refund

If you found a mistake on your return that has already been filed electronically, then you need to create and mail an amended return to make the correction.  Then you can send the correct payment amount with the amended return. 

You should not simply mail a lesser amount if you had a balance due.  The IRS will compare that amount to the return that was filed and assume that you still owe additional taxes.  

See the following TurboTax article for instructions to get started with amending your return:

How do I amend a 2019 return in TurboTax?

If you have printed your return to file by mail, you should fix the mistake and reprint it before mailing the incorrect return.  

In order to get back into your return to make changes, you will need to indicate that you are trying to Add a State.  This will open up the return again so that you can edit it.  

The step by step instructions are in the following TurboTax article, just stop after step 4 and make your changes:

How do I change from mail to e-file in TurboTax Online?

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