Closing the NSPanel issue

Question

very unusual problem i'm getting if i press the close button of panel, panel closes but when i press a custom button and calls this close function panel doesn't close. If i mark a breakpoint in close function and continue with execution then panel gets close...i'm confused. why panel doesn't close on normal execution but closes when i mark breakpoint and continue it?

NSRect panelRect = NSMakeRect(100, 100, 530, 400);
RecordsListingViewController* listController =  [[RecordsListingViewController alloc] initWithContentRect:panelRect
       styleMask:NSTitledWindowMask | NSClosableWindowMask | NSUtilityWindowMask
         backing:NSBackingStoreBuffered defer:YES];
NSUInteger modelInt = [[NSApplication sharedApplication] runModalForWindow:listController];

- (void)close
{
    ///[self stop];
    [[NSApplication sharedApplication] stopModal];
    [super close];
}