iOS - property setter works but getter does not in UICollectionViewController

I create a property placeId in UICollectionViewController. After I assign a value to it, I can't get the value in current viewController. I can't find the reason. I appreciate your help.

@property (strong, nonatomic) NSString *placeId;

-(void)setPlaceId:(NSString *)placeId{
   _placeId = placeId;
   [self.collectionView reloadData];
}

I assign a value to placeId property in previous uitableviewcontroller through segue but I can't get _placeId in viewDidLoad in UICollectionViewController.

- (void)viewDidLoad {
   [super viewDidLoad];
   self.collectionView.backgroundColor = [UIColor whiteColor];
   NSLog(@"placeid for new%@",_placeId);
   [self loadData];
}

dispatch_async(dispatch_get_main_queue(), ^{                            
     destViewController.placeId = placeId;                            
});

I appreciate your help.