Are you using the Desktop program?
Your tax return file ends in .tax2019. Search your computer for it. Check the Recycle Bin or Trash. Check in One Drive, etc. it should be in your Documents then in the Turbo Tax folder. Check your backups.
If you don't have the main .tax file you might have one that starts with a Tilde sign ~ like "~your name.tax2019". That file is if your computer crashes or your real file gets lost or deleted or corrupt so you can restore it.
Find your Tax file in Windows
https://ttlc.intuit.com/community/tax-data-file/help/find-your-tax-data-file-tax-file-in-windows/00/...
