It's probably in the formatting of the book itself. Have you tried looking at with Kindle for PC?
If you're finding it to annoying, Amazon will refund your purchase - I think you have 7 days?
Even better! You can get that book right here at MobileRead for free. The formatting is excellent, it has linked chapters, TOC, etc.:
https://www.mobileread.com/forums/showthread.php?t=18605