GetPositionAsync not work in Xamarin Android

Here is the code that I am using.
This code works on IOS but never worked on Android.
I could see some similar issues in their Project but couldn't get any help.

public async Task<Position> GetCurrentLocation()
    {
      Position position = null;
      try
      {
        var locator = CrossGeolocator.Current;
        locator.DesiredAccuracy = 100;

        position = await locator.GetLastKnownLocationAsync();

        if (position != null)
        {
          //got a cahched position, so let's use it.
          return;
        }

        if(!locator.IsGeolocationAvailable || !locator.IsGeolocationEnabled)
        {
          //not available or enabled
          return;
        }

        position = await locator.GetPositionAsync(TimeSpan.FromSeconds(20), null, true);

      }
      catch (Exception ex)
      {
        //Display error as we have timed out or can't get location.
      }

      if(position == null)
        return;

      var output = string.Format("Time: {0} \nLat: {1} \nLong: {2} \nAltitude: {3} \nAltitude Accuracy: {4} \nAccuracy: {5} \nHeading: {6} \nSpeed: {7}",
          position.Timestamp, position.Latitude, position.Longitude,
          position.Altitude, position.AltitudeAccuracy, position.Accuracy, position.Heading, position.Speed);

      Debug.WriteLine(output);
    }

I always get task cancellation exception.

    System.Threading.Tasks.TaskCanceledException: A task was canceled.
          at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00026] in <896ad1d315ca4ba7b117efb8dacaedcf>:0
          at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x00028] in <896ad1d315ca4ba7b117efb8dacaedcf>:0
          at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in <896ad1d315ca4ba7b117efb8dacaedcf>:0
          at System.Runtime.CompilerServices.TaskAwaiter`1[TResult].GetResult () [0x00000] in <896ad1d315ca4ba7b117efb8dacaedcf>:0
          at Plugin.Geolocator.GeolocatorImplementation+<GetPositionAsync>d__33.MoveNext () [0x0042a] in C:\projects\geolocatorplugin\src\Geolocator.Plugin.Android\GeolocatorImplementation.cs:206
        --- End of stack trace from previous location where exception was thrown ---
          at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in <896ad1d315ca4ba7b117efb8dacaedcf>:0
          at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x0001a] in <896ad1d315ca4ba7b117efb8dacaedcf>:0
          at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x00028] in <896ad1d315ca4ba7b117efb8dacaedcf>:0
          at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in <896ad1d315ca4ba7b117efb8dacaedcf>:0
          at System.Runtime.CompilerServices.TaskAwaiter`1[TResult].GetResult () [0x00000] in <896ad1d315ca4ba7b117efb8dacaedcf>:0
          at MtwPublicApp.Services.LocationService+<GetCurrentLocation>d__2.MoveNext ()

Please help me to fix
Thanks!