Sync problem 11.3

I tried a lot but can't get mobile and desktop sync.

I see a lot of errors (150) when ik hit the ALT key (i'm a Mac user) this are 2 error messages:

Lightroom_Fatal_SQLite_Corruption :: Database: /Users/username/SynologyDrive/LightroomCatalogus/Lightroom Catalog-3-2-v10-v11.lrcat :: Error: database disk image is malformed :: SQL: INSERT OR REPLACE INTO AgPendingOzAssetBinaryDownloads
SELECT ?, ?, strftime( "%s", "now" ), ?, ?

Lightroom_Fatal_SQLite_Corruption :: Database: /Users/username/SynologyDrive/LightroomCatalogus/Lightroom Catalog-3-2-v10-v11.lrcat :: Error: database disk image is malformed :: SQL: INSERT OR REPLACE INTO AgPendingOzAssetBinaryDownloads

How to handle?

Kind regards René