app launched more than 1 times

[Alessandro-PM]

Hello, I have 2 apps. Both have singleInstance in androidmanifest.xml.
One is a cordova app (that uses this plugin) and the other one is a flutter app.
If I call the cordova app from flutter app, the cordova app is opened only 1 time, and if it's already running the focus goes on it without opening a second instance (of course because I have singleInstance).
If i call the flutter app from cordova app using this plugin, the flutter app is opening even if a previous instance is already running, and the new instance is "included" in my cordova app, so I have 2 flutter apps. This is a problem for me, I need to have only 1 instance. Where can be the problem?