Assuming you did *not* receive a W-2 for 2018:
Under the Personal Income tab elect to start/update Wages & Salaries.
Click the DELETE button to the right of the W-2 listed there.
Click the YES button to confirm the deletion.
Click the DONE button.
Now you *MUST* elect to start/update Wages & Salaries again.
Select "We/I don't have any W-2's" and click Continue.
That does it. Run the review/final checks again and you should be good for that specific issue.