If your return has been filed and accepted, they only way to make any changes or add information is to file an amended return. The amendment form will be available on 2/28/2019 (subject to change). Amended returns must be mailed. Any refund due with an amended return is sent by check. Once the amendment form is available you can amend your return. Any taxes owed must be paid by April 15, 2019.
How to amend (change or correct) a return you already filed