Unfortunately, once you have upgraded or added features to your TurboTax return, there is no way to downgrade or remove the extra features. You would need to create a new return to use another product. 

To start a new return, select “Start a New Return” from under “My Returns” in the top left corner. When you make a new return, don't choose a return from the list to transfer, instead pick "Create A Different Return".

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.

I am not getting option to start new return

I chose full service and want to change its not letting me to to any page from there 

and my return is not opening 

@smaddel Please clear your browser cache (or use a different browser) and try again. If you are still not able to resolve this issue, please contact our phone support team for more assistance.