The YI Home camera is only compatible on a 2.4GHz band network. 5GHz networks are not supported.
All routers have a 2.4GHz band network available and most routers are dual-band, meaning they have both a 2.4GHz and 5Ghz band network. Many routers have both bands available simultaneously, meaning you can see two network names for your router. Check your Wi-Fi settings to see if you have 2 networks available. The 5GHz network name will typically end in a 5, while the 2.4GHz network might end in 2 but it may not be indicated in the name.
If you need additional help, contact your internet service provider for assistance on connecting to your 2.4GHz band network.