Make sure it's a mp4 format and not to long. Try a shorter clip if you continue having trouble with the one you have now.
I know when I upload mine it sometime won't accept it and I have to re-try several time. Once it allows it to load, it will take a couple minutes for it to fully download to the website. It will show you a percentage and how much you have left.
After it's 100% it still will have to resize the video or picture posted. Idk why but it does.
Try this during early mornings or late late night as the foot traffic on the site will be lower during this time.
Hope this helps, if not message administration and they will help you.
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