iCloud Photo Sync issues photos wont upload

I have been uploading photos to my iCloud Drive photo library using the upload feature at iCloud.com from a folder on my iCloud hard drive. Some photos wont upload because they say they are duplicates but they are not, even if I do it one by one. I completely changed the file names also and they still will not upload. I have no options to upload anyway or compare or to find the duplicate file that is causing the error. Is there a solution or work around to this problem?