@Haziq try rebooting the whole system and restart then. If you still have issues contact support, I'm sure they know how to help

Plug the power cord for the modem back in, but leave the coaxial cable disconnected. Wait 3-5 minutes and reconnect the coaxial cable. Wait for modem to reconnect and then check for IP and service.

@Haziq I sometimes have to unplug several times before it works, but unplugging is a good solution :)

When such thing happens it is usually some cord left disconnected or some key that turned off Wi-fi connectivity. Check all cords and all try manually configuring your router settings.