Asus Fonepad Note 6 - Manual (Page 56)

ASUS Fonepad E-Manual 
Turning your ASUS Fonepad off
You can shut down your ASUS Fonepad by doing any of the following:
q
Press the power button for about two (2) seconds and when prompted, tap
Power Off then tap OK.
q
If your ASUS Fonepad is unresponsive, press and hold the power button for
about four (4) seconds until your ASUS Fonepad turns off.
IMPORTANT! Forcing the system to shut down may result to data loss. Ensure that
you back up your data regularly.
Putting your ASUS Fonepad to sleep
To put your ASUS Fonepad to sleep, press the power button once.