Since you haven't actually filed, you can make changes by editing. Do NOT click on Amend, or you'll have problems.
If TurboTax thinks you were finished, your interview will be closed. To open it back up, at the Tax Home look for a link "Add a State." This doesn't really add one, but will open the return back up. If making changes on the Federal side, make sure it's reflected in the state return, if applicable. After making the changes, run the Federal and state Reviews again.
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