Form 1098 has been finalized, so not sure why you would get an error like that.
If you did not enter a 1098, you can click Federal, then click Deductions & Credits
Scroll down the list to see if a 1098 has been entered.
Additionally you can look and delete the form this way:
Sign into your account and go into the return
Open the “Tax Tools” drop-down on the left side bar
Click on “Tools” on that drop-down
Click Delete a form (the third one down) on the “Tools Center” screen
Scroll down and click “Delete” next to Form 1098
Please make sure you are not deleting something you need.
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