Make sure you do not have any pending Windows updates.If you are using Windows Hello Face for the first time, restart your computer.Before proceeding to the solutions make sure you try these workarounds on your computer. This usually means that your camera is not compatible with Windows Hello face anymore. When users try to Sign-In they get the error We couldn’t find a camera compatible with Windows Hello face. However, if the feature stops working all of a sudden then this can be a serious problem for some users.
Windows Hello allows users to Sign-In using their face through the webcam.