How can I restore the factory settings of IG502 through hardware methods?

How can I restore the factory settings of IG502 through hardware methods?

1. Within 10 seconds after the device is powered on, press and hold the RESET button;
2. Release the RESET button when the ERR light is constantly on;
3. When the ERR light goes out, press and hold the RESET button again until the ERR light starts flashing;
4. Wait for the ERR light to completely go out, indicating successful recovery. The device will be reset to its default configuration (LAN port IP 192.168.2.1, account adm/123456).