app doesn't save date to calender swift : I am trying to specific date to calendar but doesn't wok 

this is my code


I am trying to specific date to calendar but doesn't wok 

this is my code 

 

    @IBAction func addToCalenderButton(sender: AnyObject) {
        let eventStore = EKEventStore()
        self.event?.Start
        let dateString = "Thu, 24 Oct 2015 07:45"
        let dateFormatter = NSDateFormatter()
        dateFormatter.dateFormat = "EEE, dd MMM yyy hh:mm"
        let date:NSDate = dateFormatter.dateFromString(dateString)!
        dateFormatter.dateFormat = "EEE, dd MMM yyy hh:mm"
      
        
        if (EKEventStore.authorizationStatusForEntityType(.Event) != EKAuthorizationStatus.Authorized) {
            eventStore.requestAccessToEntityType(.Event, completion: {
                granted, error in
                self.createEvent(eventStore, title: (self.event?.title)!, startDate: date)
            })
        } else {
            createEvent(eventStore, title: (self.event?.title)!, startDate: date)
        }
        
    }
    
    func createEvent(eventStore: EKEventStore, title: String, startDate: NSDate) {
        let event = EKEvent(eventStore: eventStore)
        
        event.title = title
        event.startDate = startDate
        event.calendar = eventStore.defaultCalendarForNewEvents
        do {
            try eventStore.saveEvent(event, span: .ThisEvent)
            savedEventId = event.eventIdentifier
            Constant.displayAlert(self, title: "", Message: "The event has been added")
        } catch {
           print("Bad things happened")
        }
    }

