If you are using the Online version, you will have
to do a new, separate online account (with a different user ID) for
each federal return you want to prepare and purchase for each (if you need
to use a paid version of the online software). If you do another return
under the same username you did your own return, it will override the one you
already filed and lose everything for that return. It's always been this way
online.
· Start another return in
TurboTax Online: https://ttlc.intuit.com/questions/1894512
You can still use your same email address (for up to 5 online
accounts) if you want to get notifications, but the username must be a new one
for each online account you create.