Flutter is crashing my application when I try to open it with a UniversalLink

Im trying to open a specific FlutterViewController, when I close my application and try to open it with a universal link the application catch this exception: Flutter view controller 'NSInternalInconsistencyException', reason: 'Engine is required'. but im already initialized the flutter engine here in my AppDelegate.

    override func application(_ application: UIApplication, willFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
        self.flutterStart()
        return true
    }

    func flutterStart() {
        flutterEngine.run()
        // Connects plugins with iOS platform code to this app.
        GeneratedPluginRegistrant.register(with: self.flutterEngine);
}

if the app is already open everything looks good.

Use dispatch main async. check if de function is already called and if not i call it when i create the FlutterViewController.

The problems was that I was trying to run the app with flutter in debug mode:

FLUTTER_BUILD_MODE = debug

To solve the issue I just changed it to release.