Many people have multiple TT accounts and forget how to access them. Log out of the account you are in now.
Account recovery
https://myturbotax.intuit.com/account-recovery/
https://ttlc.intuit.com/questions/1901535-forgot-your-turbotax-online-user-id-or-password
Or did you use the desktop version of TurboTax? If so, the files are on your own hard drive or any backup device you used like a flash drive.
https://ttlc.intuit.com/questions/1901486-how-many-turbotax-accounts-do-i-have
https://ttlc.intuit.com/questions/1901535
https://ttlc.intuit.com/questions/1901659-find-your-tax-data-file-in-mac
https://ttlc.intuit.com/questions/1900721-find-your-tax-data-file-tax-file-in-windows
I started my 2019 return. I stopped for awhile and returned to continue my return. One of the first things I saw was, "you didn't file your 2018 tax with Turbo Tax!!! I DID file with Turbo Tax in 2018 including paying the fee and experiencing a quarterly return schedule. I couldn't get a COPY of my return because Turbo Tax didn't provide a way.
2019 has turned into a major bust!!!!!! I have been busy at my computer for 2 hours trying to "pick up where I left off. I can't get past "signing in". What a joke this is.