Classic to cloud (& vice versa) syncing problem

Hi,

i have been using a combination of Classic & Cloud via collections since this was released; very happy with it, no problems at all. Until today.......

Syncing appears to have stopped between the cloud and classic, sorry I am not very technical on this. I will give you an example......if I reject a photo using LR mobile, I can see the update on LR Creative Cloud viewed on the web via my laptop but it does not update into LR Classic also on my laptop. Also if I reject a photo in LR Classic then LR shows that it is trying to sync but it can't complete it.

i have tried deleting/renaming the sync files on my laptap. In this instance LR sincs 20,000+ photos, but is not wanting to sync any edits.

Does anyone have any thoughts on cause & solution?

Thanks Mike