It sounds like there is an issue with the book you purchased from iBookstore. You have taken some good troubleshooting steps already, and next, I recommend following the steps below to report this to the iTunes Store:
To report an issue with your iTunes Store, App Store, Mac App Store, or iBookstore purchase, follow these steps:
- Find the email receipt for your purchase.
- Click Report a Problem under the app that is having the issue.
- When prompted, enter the Apple ID and password you used to purchase the item, then click Report a Problem.
- Click Report a Problem next to the item you are having an issue with.
- From the Choose Problem dropdown menu, choose the appropriate issue.
- Follow the onscreen instructions and—if prompted—type a description of the problem into the text field.
- Click Submit to have your issue reviewed.
You can find the full article here:
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