Would suggest you to sign out of both Lightroom and Lightroom Mobile
and rename sync.lrdata to sync-old.lrdata stored at the below location :
Mac : C:\Users\Username\AppData\Local\Adobe\Lightroom\Caches\Sync Data\Sync.lrdata
Windows : /Users/Library/Caches/Adobe/Lightroom/sync Data/sync.lrdata
then, sign in back and check if the syncing is working fine.
Thank you for the responce. That doesn't seem to make a difference at the mobile device. It still says UPLOADING....523 Pending when I click the cloud, without any progress and on the WIFI.
The issue was fixed when I removed all data from lightroom desktop, deleted the app from the iphone and reinstalled it!!
Good to know that it has been resolved!