Had the same issue; autosave would not work and when trying to file electronically continued to get the warning that 'file was locked and did not have permission to access....' Could never get return to efile. After hours of checking that the files were not locked and I had permission to read and write I finally stumbled on the suggestion to check if TurboTax had been granted Full Disk Access in the Privacy setting in the Security and Privacy area under System Preferences. This solved the issue.
