How to unlock google lock on android phone after factory reset

Google FRP lock is a security feature that Google have on Android devices with Android OS Version 5.1 (Lollipop) and higher. It is a built-in security feature that protects users device and information, including screen locks and data encryptions. it helps to protect android devices from authorized use. 

This occurs automatically if a device is factory reset through an untrusted way. Normally when you wipe data/factory reset via Recovery Mode