How to notify the selection changes in Xamarin.Forms RadioButton [SfRadioButton]

public class Model : INotifyPropertyChanged
    {
        private bool isChecked;
 
        private ICommand stateChangedCommand;
        ..
        public ICommand StateChangedCommand
        {
            get { return stateChangedCommand; }
            set
            {
                stateChangedCommand = value;
                PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("StateChangedCommand"));
            }
        }
 
        public bool IsChecked
        {
            get { return isChecked; }
            set
            {
                isChecked = value;
                PropertyChanged?.Invoke(this, new PropertyChangedEventArgs("IsChecked"));
            }
        }
 
        public Model()
        {
            StateChangedCommand = new Command(OutputValue);
        }
 
        void OutputValue(object person)
        {
            if (IsChecked)
            {
                App.Current.MainPage.DisplayAlert("Message", "Selected Language", (person as SfRadioButton).Text);
            }
        }
 
        public event PropertyChangedEventHandler PropertyChanged;
 
    }
}

  <buttons:SfRadioGroup x:Name="radioGroup" BindableLayout.ItemsSource="{Binding Items}">
            <BindableLayout.ItemTemplate>
                <DataTemplate>
                    <buttons:SfRadioButton x:Name="radioButton" IsChecked="{Binding IsChecked}" Text="{Binding Item}">
                        <buttons:SfRadioButton.Behaviors>
                            <local:EventToCommandBehavior
                                             EventName="StateChanged"
                                             Command="{Binding StateChangedCommand}"
                                             CommandParameter="{x:Reference radioButton}"/>
                        </buttons:SfRadioButton.Behaviors>
                    </buttons:SfRadioButton>
                </DataTemplate>
            </BindableLayout.ItemTemplate>
        </buttons:SfRadioGroup>