UILocalNotification doesn't show - ios

Question

In didFinishLaunchingWithOptions I am making a request to a server after every 30 seconds to get Y or N using an NSTimer
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
NSTimer *notifyTimer = [NSTimer timerWithTimeInterval:30.0 target:self selector:#selector(httpRequest) userInfo:nil repeats:YES];//7200.0
[NSRunLoop mainRunLoop] addTimer:notifyTimer forMode:NSDefaultRunLoopMode];
return YES;
}
-(NSString *)httpRequest {
NSURL *url = [NSURL URLWithString:#"http:192.168.10.67/t.php"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
[request setValue:#"application/x-www-form-urlencoded" forHTTPHeaderField:#"content-type"];
[request setHTTPMethod:#"GET"];
[request setTimeoutInterval:25];
NSURLResponse *response;
NSData *dataReply = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:nil];
NSString *stringReply = [[NSString alloc] initWithData:dataReply encoding:NSASCIIStringEncoding];
if([stringReply isEqualToString:#"Y"]) {
[self showLocalNotification];
}
}
If response is Y I am registering a UILocalNotification which will fire in a second.
-(void)showLocalNotification {
NSLog("Notification is here.");
NSString *msg = #"test message";
[[UIApplication sharedApplication] cancelAllLocalNotifications];
UILocalNotification *_localNotification = [[UILocalNotification alloc]init];
_localNotification.fireDate = [NSDate dateWithTimeIntervalSinceNow:1];
_localNotification.timeZone = [NSTimeZone defaultTimeZone];
_localNotification.alertBody = msg;
_localNotification.soundName = UILocalNotificationDefaultSoundName;
_localNotification.applicationIconBadgeNumber = [[UIApplication sharedApplication] applicationIconBadgeNumber]+1;
[[UIApplication sharedApplication] scheduleLocalNotification:_localNotification];
//[[UIApplication sharedApplication] presentLocalNotificationNow:_localNotification];
}
UILocalNotification does not show notification alert to user and does not print log when application is in background.
When the application comes back into the foreground then it prints all the logs statements at once. What am I doing wrong?
Also, it is a VoIP application. and UIBackgroundMode has voip and audio set.