Crush after receving a message and calling DisplayActionSheet

Hi All,
I have really simple scenario, I have a viewModel with timer and when the timer is 0 this viewModel sends a message to the view that time has ended.

MessagingCenter.Send<ViewModel>(this, "IsTimeEnded");

and in the view:

MessagingCenter.Subscribe<PomodoroViewModel>(this, "IsTimeEnded", async (sender) =>
                {
                    var action = await DisplayActionSheet("End?", "Cancel", "", "Yes", "No", "Maybe");
                    Console.WriteLine("Action: " + action);
                });

After I put there this DisplayActionSheet application is crushing but when I have only Console.Writeline("end") everything works ok.
Please tell me why? The same thing is happened when I'm going to use DisplayAlert.