LR classic photos not syncing to LR mobile

Hello,

I just got a new pc a few weeks ago and I have been trying to get everything working from my laptop to my pc. i finally got everythign up and working and then the new LR update comes up and i can no longer sycn my photos to my LR mobile. i tried to uninstall and reinstall a older version. i was able to sync with the older version but it was from maybe 4 months ago and didnt have any of my newer work in it, not to mention with the new update the catalog is not backwards compatable. throughout this whole week ive tried everything to get it to sync and to no avail. can anyone help?