Make sure that your controller is in range of your network. Generally, if your phone can see the network, your controller should too.
If your WiFi router is set to 5ghz mode, you should either set it back down to 2.4ghz, or make sure that it is also operating at 2.4ghz. Our Residential WiFi controller operates at 2.4ghz mode because this mode offers the best range and is best able to penetrate obstacles (like walls and plants). Most routers default to use 2.4ghz, or if they use 5ghz, they also operate a separate 2.4ghz radio at the same time.