I need to change this back to my personal information. I used 2019 Turbo Tax to try to estimate my Deceased Mothers tax liability for extension. Did not work.

What did you do?   Did you use the same account and user ID for a second tax return?   If you did that then the second return overwrote the first one---the first one is lost forever.   When you use online TurboTax you need an account and user ID for each return you prepare.

What are you trying to do now---are you trying to prepare a 2020 return?   Online is only for 2020 returns---it cannot be used for any other year.   

See if you still have an account and user ID for your 2019 return by using the recovery tool.   If you overwrote your 2019 return, you will have to start over from scratch on 2020.

https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-access-my-prior-year-return/01/27010

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