To fix the number that was just typed wrong, return to the Jobs (W-2) area of your return and click the pencil icon or Edit button next to the W-2 that needs to be updated.
To do this in TurboTax, inside the program, go to the search box and enter w2. Click the Jump to link in the search results.
For more information, see: How do I import or enter my W-2?
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