In the Navigator, activate the Layout Book, select the Layout Book item at the top of the tree structure, right-click and use the "Book Settings" command to open its Dialog.
In the "Numbering of Changes in Revisions" panel, is the "Number by Revisions" radion button active? If yes, then try switching to the "Use Change ID" radio button and see if that helps.
Since this is a Layout Book setting, it will affect all Change IDs displayed in the Layout Book.
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