After researching on this issue on other forums lot of people has suggested to add this line in AppDelegate application.BeginBackgroundTask("showNotification", expirationHandler: nil); but since it is not allowed for expirationHandler to be nil anymore. I tried calling EndBackgroundTask but still notification are not working in Background mode. I also tried calling my Schedule Notification code from BeginBackgroundTask on my controller but it didn't work either. Does anyone has any idea on how to make local Notification work in background mode in IOS13.

I am using SQLite, and the issue is not with database. When ever a user go to ControllerB a timer is trigged, firing Get call every 5 sec (it keeps firing even when user go out of the screen). If there is new data available, then i save the response in database and reload the TableView (only when the user is on controllerB), and also fire local notification to alert the user that new data is available. But issue is when i got back to ControllerA and come back to ControllerB and if the service call are still being made. Need a work around to stop service call while ControllerB is being loaded.

After doing endless testing, I finally figured it out that API calls being made during view controller life cycle was causing the issue. So I removed the calls while ViewController is being loaded. Now ReloadData works fine. But actually i need those calls to fire every 5 seconds. So i cant actually remove them. Does anyone have any idea, why it does that. I need a workaround to stop Tableview.Window being nil in this situation.