SharedPreferences not working after a SplashScreen was added

HI, i have a problem i just create a simple app with one activity and on this activity i add two buttons and one edittext, on button saves data to the SharedPreferences and other read it, and display the data to the EditText, everything works fine until i add a splashscreen this is the splashscreen activity code

[Activity(MainLauncher = true, Theme = "@style/Theme.Splash", NoHistory = true)]
public class SplashScreen : Activity
{
protected override void OnCreate(Bundle bundle)
{
base.OnCreate(bundle);

        // Create your application here
        StartActivity(typeof(Activity1));

    }
}

and this the Activity1 code:

[Activity(Label = "Shared Preferences", Icon = "@drawable/icon")]
public class Activity1 : Activity
{
EditText dataEditText;

    protected override void OnCreate(Bundle bundle)
    {
        base.OnCreate(bundle);

        // Set our view from the "main" layout resource
        SetContentView(Resource.Layout.Main);

        Button saveButton = FindViewById<Button>(Resource.Id.SaveSP);
        Button readButton = FindViewById<Button>(Resource.Id.ReadSP);

        dataEditText = FindViewById<EditText>(Resource.Id.DataEditText);

        saveButton.Click += delegate
        {
            saveData();
        };

        readButton.Click += delegate
        {
            readData();
        };
    }

it works only if the app is running but as soon i stop it, and run it again, the values never get readed from the SharedPreferences.

any idea?