When Setting up Lock Screen by Fingerprint, requests of PIN/Pattern/Password appears. Why?

l Please note that the answer below is a reference for customer and which may change in different software version, the Images are for reference only, all other products and services mentioned may belong to their respective trademark owners

To use the Fingerprint function on devices based on Android OS 6.0, you need to set up PIN, Pattern or Password must be set first. This is Google’s new concept to reinforce the device security and it’s common concept for devices based on Android OS 6.0.

Accordingly, you can unlock your device with PIN, Pattern or Password which you set even if you set your lock screen as Fingerprint.