Notification Center Selector Method does not get called – Ios swift

Hi I’ve HomeCollectionViewCellComponent which is using in HomeCollectionViewCell and also there is a struct that holds size calculation logics for my collectionView (HomeCollectionViewCellSizeCalculator). it is calling in sizeForItem method of UICollectionViewDelegateFlowLayout. I hide my imageView when kingfisher is failed to downloading but I also want to compute imageSize as zero. I should tell to sizeCalculator from the setData function inside the HomeCollectionViewCellComponent. I used NotificationCenter but its objc method does not called.

HomeCollectionViewCellComponent setData func

    func setData(with data: Article?) {
    guard let data = data else { return }
    
    if let imageUrl = data.urlToImage, let url = URL(string: imageUrl) {
        self.newsImageView.kf.setImage(with: url) { [weak self] result in
            guard let self = self else { return }
            switch result {
            case .success(_):
                break
            case .failure(_):
                self.newsImageView.isHidden = true
                NotificationCenter.default.post(name: .kingfisherFail, object: nil)
            }
        }
    }
}

HomeCollectionViewCellSizeCalculator

class HomeCollectionViewCellSizeCalculator {

private let width: CGFloat
private let article: Article?
private var imageDownloadingFailed: Bool = false

init(width: CGFloat, article: Article?) {
    self.width = width
    self.article = article
    
    NotificationCenter.default.addObserver(self, selector: #selector(didImageDownloadingFailed), name: .kingfisherFail, object: nil)
}

private var imageSize: CGSize {
    return imageDownloadingFailed ? .zero : CGSize(width: width, height: HomeCollectionViewCellComponentViewConstants.imageViewHeight + HomeCollectionViewCellComponentViewConstants.imageTopSpacing)
}

@objc func didImageDownloadingFailed(notification: Notification) {
    print("didImageDownloadingFailed")
    self.imageDownloadingFailed = true
}

HomeViewCollectionViewDelegate

final class HomeViewCollectionViewDelegate: NSObject, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout {

private var viewModel: HomeViewModel

init(viewModel: HomeViewModel) {
    self.viewModel = viewModel
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
    guard let article = viewModel.getArticle(at: indexPath) else { return CGSize(width: collectionView.frame.width, height: collectionView.frame.height) }
    
    let sizeCalculator = HomeCollectionViewCellSizeCalculator(width: collectionView.frame.width, article: article)
    return CGSize(width: collectionView.frame.width, height: sizeCalculator.itemSize.height)
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
    return 15
}

}