?:0: attempt to index field 'rootFile' (a nil value)

Hello

I have 3817 "pictures" that appear grey, with no information (no metadata, no preview : nothing). I cannot do anything with these picture : none erasing option is working. When I chose one, it just does nothing : the grey rectangle is still there.

So, I installed Find Duplicates 2 plugin to scan for corrupted files, and it found the same 3817 grey pitcures. When I look at the plugin log file, the error in the Subject appears (?:0: attempt to index field 'rootFile' (a nil value)).

I tried creating a new catalog, and I have no problem importing or deleting some pictures. But When I try to import from the other catalog, it stops after importing some pictures.

I really do not know what to do...

I have 142k picture, lot of them were modified using previous versions of Lightroom, I dont want to loose my changes but I would like to get rid of these corrupted entries in my database.

I read a lot of articles about this error message, but each time it does not seem to be the same problem : people are managing to delete (at least one by one) their corrupted files. But I cannot do anaything.

Does someone can help me ?

Thank you very much

My configuration :

Version Lightroom Classic: 9.2.1 [ 202004070813-7699d98a ]
Licence: Creative Cloud
Paramètre de langue: fr-FR
Système d'exploitation : Mac OS 10
Version : 10.15.4 [19E287]
Architecture de l'application : x64
Nombre de processeurs logiques: 16
Vitesse du processeur : 3,6 Ghz
Version SQLite: 3.30.1
Mémoire intégrée : 65 536,0 Mo