Not recognizing audible book chapters

I used the audible manager software to load the files to the clip jam. Files are in .aax format and sizes range from 500mb to about 1000mb.They show up in “books/audiobooks/audible” just as expected. But when playing there is just one big chapter with a length of like 20h. There are 4 audible books on the device, so it shows “1/4” when playing the first. My old clip+ additionally displayed the current chapter number out of the total number. Pressing the forward or backward button skips to the next or previous book, rather than to the next or previous chapter as expected.

display photo