Projects not appearing after FCPX library update

I use a MacBook Air 2019 with Monterrey
FCPX is version 10.6.5

I've been trying to resume an old (2018) movie project and, after updating the library in order to edit, i cannot find the project with the edit. All the assets are in the library, but no project. I wonder if anyone could bring some light onto this situation. Thank you.

If you twirl open the top-level Smart Collections and choose Projects, are any displayed in the browser?

You could launch a previous version of FCP from your backups and open a library backup to inspect the original library. I don't recall what FCP version would've been current in the 2018 time frame.

On the outside chance this happened by accident, is it possible that the edit was actually done inside a clip?

Thank you very much for the prompt response! I'll check the suggested paths to solve the problem.

Have you resolved it?