Dropbox sync, but no notebooks

I posted this on Github as well: Dropbox sync not syncing notebooks · Issue #7305 · laurent22/joplin · GitHub

But I'm wondering if there's something I'm doing wrong or if someone knows how I can fix the problem.

On the Mac version of Joplin, I imported a bunch of notebooks from Evernote. This worked fine and all my notebooks showed up on the left side pane. I synced these notebooks with Dropbox.
On iOS, I selected Dropbox and synchronized.
All of the notes synchronized onto my device, but none of the notebooks. This means when I click "All Notes" I see all my notes, but none of my notebooks show up in the left side pane. This essentially makes Joplin useless for me.

Is there a way I can restore my notebooks on iOS?