Xamarin Forms, maps not works after click button

I have problem with loading second page. IF i debug whole project google maps not show but if i debug with other XML. I mean i add label without anything, everything works fine. if i debug project on second page google maps works.

Second page

public Mapciorek()
{
InitializeComponent();
}

protected override void OnAppearing()
{
base.OnAppearing();
MyMapa.MoveToRegion(MapSpan.FromCenterAndRadius(new Position(Convert.ToDouble(13.0291), Convert.ToDouble(80.2083)), Distance.FromMiles(0.2)));
}

App

MainPage = new NavigationPage(new MainPage());

MainPage

async private void Button_Clicked(object sender, EventArgs e)
{
await Navigation.PushAsync(new Mapciorek());
}