I still see deleted files in my Drive

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C#

google-app

I made a small program that goes through my Google Drive and deletes certain files, however I still see them when I vsisit drive.google.com. I know they were deleted since my program can't find the deleted files and Google gives me an error if I click on them. Here's an example:

//My authorized DriveService
if (_service == null)
    return;

//Clean up files older than 1 day
List<File> fileList = Utilities.RetrieveAllFiles(_service);
if (fileList.Count == 0)
    return;

int counter = 0;

foreach (File item in fileList)
{
    if (ForDeletion(item))
    {
        _service.Files.Delete(item.Id).Fetch();
    }
    counter++;
}

Am I doing something wrong or is it a problem with Google Drive not updating properly?

EDIT: Just double checked and the files no longer show up in my Drive, but considering I ran into this issue a few hours ago that's still not acceptable.