TryAccessLibraryAsyncShowSettings.cs

//open app settings to allow users to give us permission
await Launcher.LaunchUriAsync(new Uri("ms-settings:appsfeatures-app"));

//confirmation dialog to retry
var confirmationDialog = new MessageDialog($"Please give this app the {library} permission " +
                                            "in the Settings app which has now opened.");
confirmationDialog.Commands.Add(okCommand);
await confirmationDialog.ShowAsync();