If you are using a desktop, windows version, you can try
Using File Explorer and finding all the files with .tax2020 extension. Use the Search text box to do this.
Then rename the incorrect file name (not the extension).
Ensure your .tax2021 file has exactly the same name as your final .tax2020 file.
Close turbotax, and reopen it.
Hopefully, turbotax will then use the correct tax file for 2020.
NOTE: If other data from your .tax2020 file changed, you may have imported incorrect numbers for other data as well. You may want to recheck all of your forms and data that used 2020 data.
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