Why does the GmsPlace.Instance.GetDetails(PlaceId) always hang?

As the title, I ran this code in different ways, and always got hanged.
In App.cs
public App (MainActivity act)
{
InitializeComponent();
GmsDirection.Init("MY_API_KEY");
GmsPlace.Init("MY_API_KEY");

            MainPage = new MainPage();
}

1. Task.Run(async ()=>{

   var pdetails = await GmsPlace.Instance.GetDetails(gplaces[j].GPlaceId);  << hanged here.
   var geo = pdetails.Item.Geometry;  << this will not be excuted.
   

   });

2. and also I tried this:
   var pdetails = GmsPlace.Instance.GetDetails(gplaces[j].GPlaceId);
   pdetails.Wait();<< hanged here
   var geo = pdetails.Result.Item.Geometry; << this will not be excuted.

Does anyone who has experience with GmsPlace?
(Any comments are welcome.)

My development situation:
VS 2010
TK.CustomMap 1.5.1