I just had this issue last night going into this morning. I removed Lightroom, and Photoshop and then uninstalled Adobe CC from my computer. Make sure though that when you uninstall, you save your settings.
I went to the lightroom page and downloaded from here: https://www.adobe.com/products/photoshop-lightroom.html#!
Once it downloaded the lightroom, it also downloaded Adobe CC for me again and took about 10 minutes for everything to download/install and then open. It's now back to syncing.
Are you having trouble syncing from your mobile device to your computer? If so, open the app on your mobile device and check the sync status in that.
I figured it was going to be an uninstall and reinstall issue. I got with Adobe customer support this morning and let them remote into the system to figure out. It's now been fixed. I don't know what the specific steps were but I believe he ended up uninstalling and reinstalling LRCC