If your router is not Internet connected, you should turn off the NTP sync option. Once this option is off, you can also manually set a time if it doesn’t already have the correct time. These can be done using the web interface.
Alternatively, if your router can function as NTP sync server, you can change the NTP ip on the controller to use your router’s ip. The NTP ip can only be changed on the controller (by pressing and holding B3 while powering up).