iCloud video files won't finish uploading

I noticed recently that I have approximately 15 out of 45 QT videos in my iCloud account that have the uploading cloud symbol. Those that are still uploading are not accessible on all devices. I don't know what to do to fix this. All videos were uploaded to iCloud several years ago. I tried logging into iCloud through the website and uploading and the webpage kept timing out. The QT video I was testing is about 4 GB. Any suggestions on what else I could try or what is going on?