Hi there,
We're sorry about the trouble with Lightroom Classic syncing issues. Would you mind sharing the version of Lightroom Classic you are using. Please try the below mentioned steps and see if that helps.
- Go to https://lightroom.adobe.com and review the Sync Errors/Issues Album (upper right). Any unresolved syncs will show up as black thumbnails and have text instructions inside that tell you how to resolved the sync.
- After all sync is resolved in Lightroom Web, launch Lightroom Classic and allow it to absorb the changes you've made. If your syncing count hasn't changed in 60 minutes proceed to next step.
- Go to Lightroom Classic > Preferences>Lightroom Sync | Sync Activity and allow the dialog 30 seconds to refresh. Leave this dialog in place until all Uploading/Downloading/Pending Photo counts stop changing. Scroll down the list and find the stuck asset and remove it from your All Synced Photos collection. Allow time for sync to re-establish.
If you have the Backup of the photos, try removing the photos from Lightroom Classic and then import again and sync to check if that works.
Let us know if that helps.
Regards,
Tarun