All WiFi routers have a 2.4 GHz band. If the 2.4 GHz and 5 GHz share the same name, you should have no problem connecting your device you can go try to add new smart home device.
If for some reason you are having trouble connecting your device to your WiFi router you can try the following.
1. Try to install the device further away from the WiFi router, outside the range of the 5Ghz (about 15 feet away) - where your phone's WiFi status bar is not full. This way only the 2.4Ghz signal is detectable by the device.
2. You can log in to your router settings and temporarily turn off the 5Ghz band on your WiFi while you set up your device. You can turn it on again after you have set up your device.
3. You can use a mobile hotspot from a secondary mobile device to connect the device, to do that first set the name of the hotspot and the password to be exactly the same as your WiFi router name and password. Turn off your WiFi router so that the device will not try to connect to the WiFi router instead of the mobile hotspot, please note that all your other devices may try to connect to the hotspot so you may need to power some of them off. Keep both phones and your smart device close together and then connect your device using the hotspot. After it is connected, turn off your hotspot and turn on your main WiFi router, the smart device will automatically connect to the main WiFi, as they are the same name and password.
How to connect lights with spectrum wifi router
Recently we have noticed that the default settings for some of the routers from Spectrum are not compatible with our devices. You will need to change the wireless mode for your 2.4GHz WiFi band from 802.11ac to 802.11n. If you don't know how to do that, please contact the technicians at Spectrum, they can walk your through this part over the phone.
After you have changed the wireless mode, please temporarily turn off your 5G band and then connect your bulbs. You can turn on the 5G after you have connected them.