Then the problem is likely misreporting by the Settings app. Windows itself is reporting it correctly according to your screenshot.
You can try re-registering the Settings app from Option 2 here: http://www.tenforums.com/tutorials/3175-apps-re...
We see a lot of reports about Storage Usage settings misreporting files by a huge amount.
To cross-check this you can install TreeSize and get a visual picture of what's eating up drive space. See how here:
https://www.groovypost.com/howto/map-hardrive-u.... But it's likely not there.
Then check for damaged System Files: https://www.lifewire.com/how-to-use-sfc-scannow...
If it cannot repair them see Step 10 here to continue: http://answers.microsoft.com/ko-kr/windows/wiki...
If these don't fix it continue with the rest of the steps in the checklist in link just above.
If nothing else works then do a Repair Install, by installing Media Creation Tool and then choosing to Upgrade Now. This reinstalls Windows while keeping files, programs and most settings in place, and is also the most stable method to advance to the latest version. http://windows.microsoft.com/ko-kr/windows-10/m...
I hope this helps. Feel free to ask back any questions and keep me posted. If you will wait to choose if I solved your problem, I will keep working with you until it's resolved.
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