Cloud Sync problem: The Dropbox account you are logged into is different from the Dropbox desktop application account.

rekordbox 6.7.5 on macOS. Just upgraded to the Professional Plan in order to use unlimited cloud sync.

However, on activating Cloud Sync rekordbox wrongly states:

"The Dropbox account you are logged into is different from the Dropbox desktop application account. To use the Cloud Library Sync, log in to the same Dropbox account as the one on the Dropbox desktop application."

However, I am logged into the same account(s). I logged out both the Dropbox desktop application and rekordbox and then re-logged in. Still rekordbox shows the (wrong) error.

Can anybody help? (This is really such a poor and frustrating user experience...)