You might encounter an error in the MyCircle app when you first open it up saying that "It looks like you aren't connected to a network with Circle on it. Please connect to a Circle-enabled network to continue."
This error loads when the MyCircle app isn't able to detect a paired Circle on the network you're on. Make sure you're connected to the network you paired Circle with. If you are, plug in Circle via ethernet and then give it a reboot and try again.
It's possible to also see this error if you haven't set up Circle yet. To do so you'll need to download the Circle Home app, turn on the Circle device, and then open the Circle Home app.