how can I know which photos are to be synchronized and solve the problem ?

Hello,

My LRC catalog have many remaining unsynchronized photos (here 2375, see screen copy included here). I do not know which are theses photos. Is a possibility to know these photos and understand why they're pending so long?

I use Lihtroom classic (LRC) Version 13.5.1 on a windows 10 and windows 11 PC.

 And th Lightroom on line I use is Version 7.5

Thank You for help