For the Wi-Fi Timer feature to work correctly, the system time on the router must be synced with the system time on the network server.

The following circumstances may prevent the Wi-Fi Timer feature from working correctly:

1. If the time you schedule the Wi-Fi to be off includes your current time, the Wi-Fi will not turn off for the current clock cycle. Instead, it will turn off at the scheduled time during the next clock cycle.
2. If the router restarts during scheduled off times, the router will automatically turn on Wi-Fi. The Wi-Fi Timer feature will be effective again during the next clock cycle.
3. After the router restarts, if the system time on the router fails to sync with the system time on the network server, the Wi-Fi Timer feature will be unable to work correctly.
4. After syncing, the router's system time will be the same as the network server time, which may be not the same as the time on the clock in your home or on your phone.