LRC Syncing, collection issues

I am having issues with LRC removing photos from a collection. I want to move all of my finished photos to a collection for sharing. I added the first 18 with no problem. Now when I add new photos to the collection , they will add and show syncing. When I come back some time later it has removed all but the origonal 18 photos from the collection. I have deleted the collection from both LRC and LR Web, and still the same thing happens. My syncing icon has also been stuck on 20 photos for about a week. Any help would be appreciated. Thank you