Ios Mac Catalyst无法在相册中保存图像，但不会产生错误

我正在将一个应用程序移植到Catalyst。在Catalyst环境下，该应用程序具有将屏幕截图保存到命名相册的功能，在纯iOS环境下，该应用程序可将屏幕截图保存到相机滚动。该代码运行良好，生成的“成功”代码没有错误。如果我查看集合的估计资产数量，它会在每次尝试后增加。但是，在“照片”应用程序中查看时，相册中没有任何内容我的截图在哪里？ 以下是相关代码：

func insertImage(image : UIImage, intoAssetCollection collection : PHAssetCollection) {
    PHPhotoLibrary.shared().performChanges({
        let creationRequest = PHAssetCreationRequest.creationRequestForAsset(from: image)
        let request = PHAssetCollectionChangeRequest(for: collection)
            if request != nil && creationRequest.placeholderForCreatedAsset != nil {
                request!.addAssets([creationRequest.placeholderForCreatedAsset!] as NSFastEnumeration)
            }
        },

        completionHandler: { (success, error) in
            if error != nil {
                print("Error: " + error!.localizedDescription)
                DispatchQueue.main.async {
                    let ac = UIAlertController(title: "Save error", message: error!.localizedDescription, preferredStyle: .alert)
                    ac.addAction(UIAlertAction(title: "Done", style: .default))
                    self.present(ac, animated: true)
                }
            } else {
                DispatchQueue.main.async {
                    let ac = UIAlertController(title: "Save success", message: "Image saved", preferredStyle: .alert)
                    ac.addAction(UIAlertAction(title: "Done", style: .default))
                    self.present(ac, animated: true)
                }
            }
        }
    )

专辑集来自：

func fetchAssetCollectionWithAlbumName(albumName : String) -> PHAssetCollection? {

    let fetchOption = PHFetchOptions()
    fetchOption.predicate = NSPredicate(format: "title == '" + albumName + "'")

    let fetchResult = PHAssetCollection.fetchAssetCollections(
        with: PHAssetCollectionType.album,
        subtype: PHAssetCollectionSubtype.albumRegular,
        options: fetchOption)
    let collection = fetchResult.firstObject

    return collection
}