Are you trying to access your 2019 return that you prepared on your computer?
If you used the desktop CD/Download editions installed on your computer, the only copy of your tax data file and any PDF's will be on the computer where the return was created. TurboTax does not store any returns completed using the desktop editions. When you use Desktop, be sure to download a copy of the return you prepared so that it is readily available.
Unless your filed your 2019 return late, or made recent payments on your 2019 liability, it is too late to amend a return even for California where the statute of limitations is 4 years instead of 3 as it is for Federal returns.