Please sign out of Lightroom and quit Lightroom.
Try to sign back in and check for the issue.
Also, please check and confirm the version of Lightroom you are using.
Which operating system are you using?
When I open LR again, there is no change. I have LR 2015.3 with Windows 10. It started syncing again and about 30 fotos of about 40 were synced and then it stopped again.
Please follow the below steps and see if this helps.
> Launch Lightroom
> Click on Edit > Preferences
> Click on Lightroom Mobile Tab
> Click on Delete all Data
> Click on Ok
> Quit and Relaunch Lightroom
Let me know if this helps.
Thank you. It helped but did not cure the problem. It synced about 40 fotos and then stopped again. There is some sort of issue. Earlier it worked perfectly.