This usually comes up when there is an amount in box 10 of the 1098-T. It usually means that you must reduce the amount in box 1 of your 1098-T.
If you don't know what it is, you probably made a mistake entering data. if you can't find the error, delete the 1098-T and start over.
Go through the entire education interview until you reach a screen titled "Your Education Expenses Summary". Click delete next to the student's name. You'll then get the "Your Education Expenses Summary" screen again. Click the "Add a student" button.