Same Issue, cannot use any of the 20% Books on any of my characters (including the one that originally got the books from the Hyper Express. These things have a duration limit on them, please find a fix soon as they expire in 2 weeks.
Server: Avesta - Us East
They worked perfectly fine up until the Main September patch a week ago. Was able to use them on the character that got them AND on different characters as well.
As my colleague said in the post above yours please refer to this post linked to clarify the situation and they can see all this information you share with us and the new issue that happen to you with the Hyper Express Honing Tomes.