This sort of sounds like an issue I was hitting for a while that turned out to be caused by a very large attachment that wasn’t syncing. I was able to see the problem file in the logs file: Uploading a large resource (resourceId: xxxxx, size:103089014 bytes) which may tie up the sync process. I am not sure that yours is the same issue, but sounds like it could be. More details on what I was seeing: Issue syncing tags, some notes, folders between Mac and iOS