You can erase your return and start from scratch as long as you haven't submitted payment or registered.
- Sign out of the mobile app (under App Settings).
- In your web browser, use your app login to sign in at TurboTax.com and select the Take me to my return button.
- On the welcome back screen, in the left-side menu, select Tax Tools, and then select Clear & Start Over (click or tap the 3 lines in the upper-left corner if you don't see this menu).
- Answer Yes in the pop-up to confirm.
- Select Sign out at the very bottom of the left-side menu.
- Now sign back in to the mobile app, and you'll start with a clean slate
https://ttlc.intuit.com/questions/3177005-how-do-i-clear-and-start-over-in-the-mobile-app
