Moving folder to another workspace results in a server error

Moving folder to another workspace results in a server error

Hey, I am trying to move all my notes in a folder (3000-4000 note) to another workspace but, shortly after, a message pops up saying internal server error, unknown error
 (error when transfer to workspace)! What to do now? Seems Nimbus can't handle all my notes which I imported from Evernote?

Thanks