Resolved. In the app, all UI elements was created manually and all ViewController inherited from a BaseViewController, including MainMenuViewController. a. the code caused the issue: @interface BaseViewController: AVPlayerViewController b. modified code: @interface BaseViewController: UIViewController Why the base ViewController inherited from AVPlayerViewController, because there's a VideoViewController that will be used to play video. unfortunately, OC don't support multiple inheritance, so I have to embed the base ViewController's functions into VideoViewController instead of inheritance. It's an issue caused by not being careful enough when modifying code.

The app does not use storyboard, actual code in product: (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { UIWindow *window = [[UIWindow alloc] initWithFrame: [[UIScreen mainScreen] bounds]]; mainMenuViewController = [[MainMenuViewController alloc] init]; navigationController = [[UINavigationController alloc] initWithRootViewController: mainMenuViewController]; window.rootViewController = navigationController; self.window = window; [self.window makeKeyAndVisible]; return YES; }