Weird log entry
Thank you for opening the thread regarding this issue.
I've checked our internal databases, and this error matches 2 known issues, and both are related to the SyncMe functionality. In both cases the error can be disregarded safely, it takes a bit of time to complete the synchronization.
Currently our Development team is working on upgrading the Synchronization functionality, and fixing the problems. It's going to be included into the future updated, but unfortunately we do not have any ETA when exactly.
Should you need anything else or have any further questions - feel free to contact us at your earliest convenience, we will be happy to help you!