SLM lab book, Kindle feedback?

Foundations of Deep Reinforcement Learning: Theory and Practice in Python (Addison-Wesley Data & Analytics Series) 1st Edition, Kindle Edition
(Laura Graesser, Wah Loon Keng)

I am interested in purchasing above book for Amazon Kindle.

When viewing the free sample:
-at the end of section 1.1 (formally defining states actions and rewards) there are missing math symbols in the text replaced by a “question mark in a box”.
-This happens again in the beginning of section 1.2 below the aside on “MDP and POMDP”

Has anybody purchased this book?
-Are the symbols still missing in the purchased full book?
-Are there any avid kindle readers who have noticed corrections to this sort of issue in other books that they own? (I do not have many kindle books)

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