Ipod Nano 6th Generation - audio books - Catalina

I followed all the steps to transfer my audiobooks through the finder onto my IPod nano 6th Generation from my MacPro Air (which has the new Catalina operating system) -- I tell it to sync (it tells me it's syncing), but no books move onto my Ipod.

This all worked great with before I put Catalina onto my laptop. Any help?