My plug shows in the App when my smart device is connected with home router, but it disappears when I am out. How to fix it?

Announcer:ECO Plugs Time:2017-10-31

If you can’t see your plug once the smart device disconnected the home router,
Please check Cloud function of the plug on the smart device.
You can see the option for activating Cloud in the plug's setting page. 
Video:  ECO Plugs - Cloud Function