First, make sure that the hub has been reset and has been removed from any previous Sengled accounts.
Your mobile device must be connected to the 2.4 GHz Wi-Fi network (5 GHz connections are not supported) of the router that you are pairing with your hub.
If your mobile device is on a different network or is using cellular data, the pairing process will not work.
After that, we would recommend trying the suggestions in in this article.