It is very messy and difficult to remove the embedded "spouse stuff" from an account. It is best to start a new account with a different user ID than to use an old account that has been used for past joint returns. Using the old account will cause errors as you work on your return.
https://ttlc.intuit.com/community/using-turbotax/help/how-do-i-start-another-return-in-turbotax-onli...
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