Error: “Convenience Unlock Is Unavailable” When Using Touch ID or Apple Watch Unlock on Mac

If you receive the Convenience Unlock is unavailable error, please check and confirm that you can unlock your Mac with Touch ID or Apple Watch first.

Then, if that works, you can use it to unlock a Strongbox database. It is a prerequisite that you can login in to your Mac using these methods before you can use them in Strongbox.