Just for reference, if the Face Unlock Accessibity setting is not available and says "Restricted Setting", you can use the following (found on XDA Developers):
Go to apps --> face unlock. Press on the 3 dots on the right upper corner and allow restricted settings
Just for reference, if the Face Unlock Accessibity setting is not available and says "Restricted Setting", you can use the following (found on XDA Developers): Go to apps --> face unlock. Press on the 3 dots on the right upper corner and allow restricted settings