Camera Upload issues (iOS Client & WD PR2100 Server)

My camera upload was working properly transferring pics from IPhone to WD NAS PR 2100. But now it is getting stuck at one video and not proceeding. Therefore I am not able to upload the remaining 100 odd pics to the server. Please advise.

The problem fixed itself when updating the pr2100 plex server with the plex pass version. I updated the wd server with the plex pass version and the uploads started syncing again.