iTunes/iBook does not completely sync my 2-part audiobook
I have a two-part audio book in iTunes that I downloaded as an MP3 from Audible a few years ago. I've attempted to drag/drop the book into my phone (yes, I see a red 2 being dragged over) and I also clicked the box next to the book in the list under Sync Audiobooks in the phone settings in iTunes. All I see in iBooks on my iPhone 6 is the first part of the book. I have the latest update for the iOS. There is over 9GB of space available on the phone and the file not syncing is only 78MB.
iPhone 6, iOS 9.3.2