I'm getting the MissingPluginExecption as well but continuously every time the user leaves the app but doesn't fully close it. This is my use flow:

1. start the app
2. use the plugin functionality (everything works fine)
3. leave the app (eg. with home button or back button of your phone)
   start the app again
4. MissingPluginExecption when trying to use the plugin function
   If I close the app and restart it everything works fine but for that special usecase it doesn't.

flutter clean did not fix this.
Is there a way to fix this?