All the way back in Android 5.0 Lollipop, Google added a ‘Trusted Face’ mode to Smart Unlock, giving all devices a slightly-secure way of unlocking with the front camera (the easily-fooled face unlock in Android 4.0 doesn’t count). However, many people on the latest Android Q beta are having issues with it. If you’re in that group, don’t worry, there’s a fix you can try.

There are already dozens of reports across Reddit and other sites of Trusted Face mode not working, even after disabling and re-enabling it again from the Settings app. Some even speculated that Google was removing the existing face unlock method to prepare for the Pixel 4’s more advanced equivalent. However, the apparent removal seems to be nothing more than a bug.

read more at https://www.androidpolice.com/2019/08/09/smart-luck-trusted-face-android-q/