Tap twice to quickly turn off the screen without pressing the power button.
The method to tap twice to turn off the screen on Asus Zenfone 4 Max ZC520KL is as follows:
Step 1: Go to ZenMotion settings.
Access ZenMotion settings
Step 2: Access touch gestures.
Access touch gestures
Step 3: Activate the feature.
Activate the function
That completes your setup process. Wishing you all success.