EKEvent alarm AlertView disappears in less then a second - iphone

Question

Event is successfully added with alarm that plays ten seconds (for testing purposes) before event start time. Problem is that alarm triggers (UIAlertView on iPhone shows) but it dissapears in less then a second. Very strange...
What could be the problem?
Code:
- (IBAction)addEvent:(id)sender {
EKEventStore *eventStore = [[EKEventStore alloc] init];
if ([eventStore respondsToSelector:#selector(requestAccessToEntityType:completion:)])
{
[eventStore requestAccessToEntityType:EKEntityTypeEvent completion:^(BOOL granted, NSError *error)
{
EKEvent *anEvent = [EKEvent eventWithEventStore:eventStore];
anEvent.calendar = eventStore.defaultCalendarForNewEvents;
anEvent.title = self.eventNameTextField.text;
NSDate *date = self.datePicker.date;
anEvent.startDate = date;
anEvent.endDate = date;
NSMutableArray *myAlarmsArray = [[NSMutableArray alloc] init];
EKAlarm *alarm1 = [EKAlarm alarmWithRelativeOffset:-10];
[myAlarmsArray addObject:alarm1];
anEvent.alarms = myAlarmsArray;
NSError *eventError;
[eventStore saveEvent:anEvent span:EKSpanThisEvent error:&eventError];
}];
}
}

Answer 1

see the following code hope it will help you.
EKEventStore *eventStore = [[EKEventStore alloc] init];
EKEvent *event = [EKEvent eventWithEventStore:eventStore];
event.title = [NSString stringWithFormat:#"%#'s Birthday",strName];
NSDate *twoYearsFromNow = [NSDate dateWithTimeIntervalSinceNow:1577846275];
double alarmAmountInSeconds = 60*60*9;
EKAlarm *alarm = [EKAlarm alarmWithRelativeOffset:(1.0*alarmAmountInSeconds)];
EKRecurrenceRule *recurrance;
recurrance = [[EKRecurrenceRule alloc] initRecurrenceWithFrequency:EKRecurrenceFrequencyYearly interval:1 end:[EKRecurrenceEnd recurrenceEndWithEndDate:twoYearsFromNow]];
NSMutableArray *arrayReccurence = [NSMutableArray arrayWithObject:recurrance];
event.recurrenceRules = arrayReccurence;
event.startDate = startDate;
event.endDate = [[NSDate alloc] initWithTimeInterval:600 sinceDate:event.startDate];
event.allDay = true;
event.alarms = [NSArray arrayWithObject:alarm];
[event setCalendar:[eventStore defaultCalendarForNewEvents]];
NSError *err;
[eventStore saveEvent:event span:EKSpanThisEvent error:&err];