Smart LED Lights Cause Internet on PC to Stop Working

If it's specifically when connecting the bulbs you see the issue it's like something with the settings on those is conflicting on the home network. It may be best to speak with the manufacture's technical support for further assistance. As for your gateway settings, the 2.4Ghz and 5Ghz share the same network name by design so as to encourage primary use o the 5Ghz radio. If you connect a device that doesn't support 5Ghz it will still work using the 2.4Ghz radio.

-Chris