Part of an Audiobook in Books is missing

I recently purchased an Audiobook via books. Listening to it I realized that there are two places where the book skips forward.

The reader stops half sentence and the next read chapter begins.

The file goes on with no seconds skipping e.g. after 2‘47“ follows 2‘48“ - however the content for the listener is missing.

The chapter length is well within the lengths of the other chapters (3‘02“ in the faulty, all others are between 3‘01“ and 3‘08“).

I see nothing how to reload a faulty file.

And is it possible that this is a faulty file on my iPhone? Or is it rather a mistake that sounds like it that originated in the conversion on the author‘s side or Apple‘s side? If so, what to do?

I realized that in the file in books there is an additional dot at this time point. Looks like the dot at which time the audiobooks is currently. Just that there is never a second dot in other files. See screenshot.

So Books seem to realize that something is odd? Or is that just a marker that there is a real book chapter starting there? (After skipping maybe minutes at the end of the last book chapter.)

Thanks for hints or solutions.