Got this from wired.com
Sometimes smart home devices that can only connect to the 2.4-GHz band have issues with mesh systems and routers that don't allow you to split bands. It's a common enough problem, but Eero has a built-in solution. Open the Eero app and go to Settings > Troubleshooting > My device won't connect and select My device is 2.4 GHz only and your Eero system will temporarily pause the 5-GHz band to help you get connected.
I haven't got an eero to try but worked with my new router. which doesn't allow split bands. Just went in settings turned off 5ghz set up home plugs and cameras turned 5ghz back on all work perfectly now.
