[JavaScript Error: "Error(s) encountered during statement execution: database disk image is malformed" {file: "resource://gre/modules/Sqlite.jsm" line: 807}]

Not sure what messages you're referring to — we'd need you to provide the exact messages — but it looks like your database is corrupted. This is usually caused by storing the Zotero data directory in a cloud storage folder or external disk that was unmounted incorrectly.

You can try running your database through DB Repair Tool. If that doesn't help, you would need to restore from a backup or, if your data and files are all online, close Zotero, delete zotero.sqlite in your data directory, restart Zotero, and sync to pull down all your data from the online library.