private async Task SendNotificationDeclinedAsync(long ticketId) { var confirmInfo = DataAccess.GetApproveConfirmInfo(ticketId); var client = new SendGridClient(ConfigurationManager.AppSettings["OneSignalApiKey"]); OneSignalNotification myNotification = new OneSignalNotification(); myNotification.contents = "Your Lottery Ticket: " + confirmInfo.LotteryNumbers + " have been declined !"; myNotification.small_icon = "icon.png"; myNotification.include_player_ids = new List <string> { "OneSignal_playerid_fordevice", "Another_onesignal_playerid" }; await myNotification.Send(); }