iOS Dev cannot delete Calendar event using eventIdentifier programmatically

Question

I can save event into Calendar user

    do {
try self.store.save(event, span: .thisEvent, commit: true)
    self.addedEventId = event.eventIdentifier
    print("\(self.addedEventId) has been added")
  }
  catch let error as NSError {
    print("\(error.localizedDescription), userInfo: \(error.userInfo)")
  }

it saved the event, and print eventIdentifier

61211649-CED1-4C74-A140-843AE0C38F44:8B7BDC14DD804F069D455E7B8F3534EF0

but when I try to delete the saved event using

if let eventToRemove = self.store.event(withIdentifier: self.addedEventId)
  {
    do {
      try self.store.remove(eventToRemove, span: .thisEvent)
      print("\(self.addedEventId) removed")
    } catch let error as NSError {
      print("\(error.userInfo)")
    }
  }

Seems I cannot find the event using eventIdentifier, the error I have from the console reads

Error getting event with identifier 61211649-CED1-4C74-A140-843AE0C38F44:8B7BDC14DD804F069D455E7B8F3534EF0: Error Domain=EKCADErrorDomain Code=1010 "(null)

Answer 1

After half day research, I finally found a way around is instead of using eventIdentifier, using calenderItemIdentifier