Since December 2020 last year, third party plugs such as GoSund Smart Plugs connected via Smart Life or Go Smart App through Amazon Alexa Skills stopped working.
You need to disable the skill then re-ensbled it again via the Alexa App to make it work. It works for a few days or minutes, then it will become unresponsive again.
Relinking, uninstalling then reinstalling the app will fix it temporarily then it will become unresponsive again.
GoSund or Alexa support will just suggest the common troubleshooting methods that I mentioned. So if you encountered the same issues as I am, then just do the basic troubleshooting methods I mentioned.
There’s no absolute fix yet. I suggest if you’re new to Alexa / Amazon Echo devices, just buy the official smart plugs. My official Amazon smart plug didn’t stop working when all else aren’t working.
Third party smart plugs still work via their respective apps. It just doesn’t work seamlessly via voice commands through Alexa.