Navigation pages has disappeared

The pages exist but are no longer in the navigation. Do you know if it is possible to restore this navigation?

Omeka 4.04
Modules :
Advanced Search (3.4.14), Archive Repertory (3.15.16), Block Plus (3.4.19), Blocks Disposition (3.4.2.3-beta), Bulk Export (3.4.29), CSSEditor (1.3.1), CSV Import (2.5.0), Clean Url (3.17.7), Contact us or author and report (3.4.11), Custom Vocab (2.0.2), EU Cookie Bar (3.4.4), Easy Admin (3.4.15), File Sideload (1.7.1), Generic module (3.4.45), Guest (3.4.20), Guest Api (3.4.4), IIIF Server (3.6.14), Image Server (3.6.14), Internationalisation (3.4.12), Log (3.4.19), Mapping (1.10.0), Metadata Browse (1.6.0), Reference (3.4.46), RestrictedSites (2.3), Universal Viewer (3.6.8), ViewerJS (3.4.0.3-0.7.2)

The navitation is stored in a cell of the database. If an issue occurs when the data is written in the table, it can be emptied. But i don’t know any cases where it arrives, because database are designed to avoid such an issue. So in that case, the best way is to recreate the navigation menu or to restore it from a backup.
Or if your menu is very big, the simpler way is to create it via a spreadsheet, to convert it to json and to copy it in the database directly. Or to develop a specific module for your needs.

Thanks, I managed to restore the situation by restoring an older database.