See https://bugs.mojang.com/browse/MCPE-29752 for details. The changelog says that this bug got fixed, but it didn't. Still occurs.
MCPE-34895
Book and Quill still breaks blocks inintentionally
Resolved
Duplicate
0
(Unassigned)
Unconfirmed
Phone - Android - Samsung Other (Specify in description)
Android 7.1
1.6.0.1
Retrieved
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-29752.
Please add a vote and any new information to the main ticket, which will be updated accordingly.
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