Did you check your credit card statement to see if you got charged anything? If it doesn't let you clear and you haven't paid or filed you could just start a new account. Online is only good for 1 return per account. But you can use the same email address for 5 accounts. Start another Online return here. Sign up and start a new account.
https://turbotax.intuit.com/personal-taxes/online
Or you will have to go back though your return and manually change anything wrong. Why do you want to restart?
