I need some help about GeoLocation function[Solved]

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C#

geolocation

I want take people location who use my program. But I cant access. Because I havent allow for this function.
There is my code. How can I access?

public async void KoordinatBel()
       {
           Geolocator location = new Geolocator();
           try
           {
               location.DesiredAccuracy = PositionAccuracy.High;
               Geoposition pos = await location.GetGeopositionAsync();
               var lat = pos.Coordinate.Latitude;
               var lang = pos.Coordinate.Longitude;
               MessageDialog yeni = new MessageDialog(lang.ToString() + ' ' + lat.ToString());
               yeni.ShowAsync();


           }
           catch (System.UnauthorizedAccessException)
           {

           }
       }

thanks in advance