The screenshot of the parental control settings page: The spent online time (befor power cycle): The spent online time (after power cycle):

On Parental Control page I setup time limitation per day. After this time the access stops. It's good. But if I reset the router (power off/on) it also resets the timer and the access is not blocked.

My Archer C6 resets the timeout in Parental Control after power down and power up again.