Are you using the desktop download? If you are using the download you can prepare and e-file up to five federal returns and the returns for one specific state of your choosing.
If you are using the online software
When you use Online TurboTax, you get one return per fee. Each return needs its own account and user ID. If you use the same account and user ID for a second return, you overwrite the first one and lose it forever.
https://turbotax.intuit.com/personal-taxes/online/
https://ttlc.intuit.com/community/using-turbotax/help/how-do-i-start-another-return-in-turbotax-onli...
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**