It keeps them for years. I have them going back 10 years. You might have used a different user id.
How to view all your accounts
https://ttlc.intuit.com/turbotax-support/en-us/help-article/account-management/many-intuit-accounts-...
It's common to end up with multiple accounts. First LOG OUT of whatever TurboTax account you're logged into right now. Then use this TurboTax account recovery website to get a list of user ID's for an email address. Run the tool against any email addresses you may have used
https://myturbotax.intuit.com/account-recovery/
