If you have attempted to pair a device multiple times with no success, the first thing you should do is restart the Hub by pressing the Reset button on the back of the device so that it re establishes a 4G cellular connection.
Once the lights return to two (2) green lights, continue with pairing devices.
If this has not helped, it is possible the hub is not establishing a strong 4G cellular connection. Move the hub to a different outlet closer to a window.
Once the hub is plugged back in and has two (2) green lights, you may attempt to pair again.
If none of these tips lead to a successful pairing, contact the Propify Smart Home Team at 866-833-0449.