Yes, TurboTax Online automatically saves your work as you progress through the tax interview. When you sign out your progress will be saved and you can sign back in and file your return at a later time. Even though you only use one email address, it is still possible that you have an additional account. Sounds like you may have created multiple accounts. You can check to see if you may have multiple Intuit accounts by following the steps in the below help article.
How many Intuit accounts do I have with TurboTax?
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