Moving to correct Forum space.
It sounds like the library may have become corrupted. Can you try creating a new library, moving a couple of your assets into it, letting it sync, and then checking to see if you can see those assets on the desktop and on the web (at Adobe Creative Cloud)? Here's how to create a new library:
* Either online at https://assets.adobe.com/assets/libraries and in the upper right hand corner under Actions choose Create Library or in Capture by tapping on the library name in the upper nav, then in the library menu that opens tap + Create New Library from the pop-up menu.
* Once you have the new library you want, the easiest way to move an asset into it is to duplicate it then move it. Tap on any asset you want to move. Once it opens in the Preview screen tap on the three dots in the upper right hand corner. Tap Duplicate. A pop-up menu will open and in it you'll have the ability to choose the library you want to move it into. Move it to the new one.
* Once you have one or two of your Capture assets moved, make sure you're over a good wireless connection (so the new library can sync to Creative Cloud), then log in to https://assets.adobe.com/assets/libraries and see if you can see that new library and the assets in it. If you see them there, check the desktop app.
Please let me know how things go.