Please double-check the features under both free and deluxe to make sure that you can use the free version of TurboTax. Please visit this link to TurboTax online. Scroll down, and click on "View all features". For example, if you want to use this feature "Finds the optimal split for donations, medical, employment expenses, and more" then you need to use the Deluxe version.
If you are sure you can use the free version of TurboTax for your tax return then:
You would need to create a new return to go back to the original product.
To start a new return, select “Start a New Return” from under “My Returns” in the top left corner. Once you have started your new return, you can select “View All Returns” from under “My Accounts & Returns”. Then delete the unwanted return by clicking the small Trash Can next to it or “Delete” under the return’s name.
Thank you for choosing TurboTax.