You answered a question incorrectly when entering them as dependents. Go back to My Info and carefully review your answers for each child.
For a child under the age of 19, you should indicate that they lived in your home for the Whole Year. That they did NOT provide over one-half of their own support. That they were full time students. That no one else in the household provided for their support. And that you did Not check the box "not valid for employment" when entering their Social Security numbers.
If your answers are correct then delete them as dependents and re-enter.
