Mobile creation/Creative Cloud Not Sync

only files in the local cc sync folder will be disappearing online.  they'll remain on your local folder (though it's been, or will be, renamed).

otherwise, 

use a web browser to navigate to the following locations. at each location there are several folders/link to check.:

https://assets.adobe.com

https://lightroom.adobe.com

https://documentcloud.adobe.com

https://spark.adobe.com

if you delete anything from any of these locations, check for a deleted folder where your file(s) was (were) moved. if you want to clear space you must delete files in the deleted folder. the used storage shown at each of those four sites (when totaled), should match the space shown used by your cc files.