In order to add missed income, you'll need to amend your return.
From How do I amend my federal tax return for this year?, here is how to amend an accepted return in TurboTax Online:
- "Go to Tax Home, scroll down to Your tax returns & documents and select the year you want to amend.
- At the amend (change) return dropdown, choose Amend using TurboTax Online.
- Follow the steps, making your changes, and carefully answer the remaining questions to finish amending your return."
Here is some more information on filing amendments: How to File an Amended Tax Return with the IRS
