Synchronization Deleted most of my Notes

[laurent]

Also please check this post as several other methods to recover notes are described:

How to recover your notes

If you lost notes or content, there are multiple ways to recover them: From the note history If the note is still there but doesn't have the content you expect, you may be able to restore it using the Note History feature. In the desktop app, click on the "i" button, then click on "Note revisions". From there, see if you can restore the content. From the trash If you manually delete a note or notebook, it will be moved to the trash folder - check if it's there. From the built-in backup By def…

(I've just added the one mentioned by personalizedrefrigerator)