There is a lot of info on the net, here is just one.
Windows 10 keeps a log of all updates that you perform either automatically or manually. It doesn't care if these updates were installed successfully or failed, it just keeps a log of these updates. This way, even the failed updates take up some space on your hard drive. In this article, we will...
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I would do an image before doing any thing.
Check update history to see if has indeed installed.
Wait a while as windows will try again to install it.
See if any of this helps.
I had similar once and deleted the contents sofwredistribution folder after stopping the service