Hi @imrukhan, the parental control should work as per instructions in the link. Please make sure that your modem is set to the correct time for your timezone for the parental controls to function correctly.
Also some devices (IOS, Android, Windows 10) employ a function called MAC address randomization. This means that every time the WiFi device is restarted, it sends a random MAC address to the DHCP server (in this case the C1200) .
As the parental controls are based on matching client MAC addresses, this causes the parental controls to fail.
Time settings are configured under Advanced -> System Tools -> Time Settings
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