Hello,
This seems related to, TorBrowser 12.5.6 no longer flagged by Windows Defender
Please try what is mentioned in that thread, but, since there is a newer version of Tor Browser available I would recommend making a fresh install of the latest version of Tor Browser (i.e. Tor Browser 13) instead.
For that, please uninstall what you have right now:
- Locate your Tor Browser folder or application. The default location is the Desktop.
- Delete the Tor Browser folder or application.
- Empty your Trash.
…and then make a fresh install, INSTALLATION | Tor Project | Tor Browser Manual