LANGTONINFO.COM no service after ordered book fell apart internet Internet

The book I ordered and received from LANGTONINFO.COM, CAMBRIDGE EDITION, "On the fourfold root of the principle of sufficient reason" is falling apart, even after using it for 2 days while using it on a book stand, which is very strange indeed. Already after receiving these copies with a plasticky feel and look, I was definitely not impressed (opposed to the 2  books I received with a cloth/linen feel), but since it is about the content I let it slide. Now it can not even hold the content nicely together, I feel compelled to complain. Basically what happened is; when I lifted the book up from the stand the front board came loose (unhinged) from the spine of the book, from head to tail, so I was looking at the fully exposed spine of the book. This has never ever happened to me. I also noticed that the quality of paper, used for the 5 different books are inconsistent, a minor detail but the more unsettling since it is published by a renowned university (Cambridge). I wonder how students deal with the falling apart issue since they put the books through a lot more mileage and abuse by traveling with it in their bags etc. Please give me your experience, advice and opinion in this matter, since I was hoping to keep these books for posterity's sake as well :) Their response >>>  "I'm sorry to hear about the problem with your item. You would have to contact the manufacturer about warranty claims, we can only offer refunds or replacements if the item comes damaged. Sorry I couldn't have been more help" Obviously the book came damaged and flawed, otherwise it would not fall apart after 2 days use. I have carried books with me, around the world, the last 30 years without a single problem.

I wonder what Mr. Schopenhauer had to say about this with the "law of causality" in mind. FORGET ABOUT LANGTONINFO!!