LR CLASSIC - Book module - Changing a page layout deletes the rest of pages to the end

Adobe LR Classic 14.1.1.

PC:

Procesador Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz 2.59 GHz
RAM instalada 16,0 GB (15,8 GB usable)
Windows:
Edición Windows 11 Home
Versión 24H2
Instalado el ‎05/‎12/‎2024
Versión del sistema operativo 26100.2605
Experiencia Paquete de experiencia de características de Windows 1000.26100.36.0

PROBLEM with BOOK MODULE - when changing the layout of a page (i remeber the last was a 2 pages layout), the program deletes all pages to the end, including the last working pages and INCLUDING the last page with the WORD BLURB. You can try to add new pages but when you exit Book Module (e.g. to GRID) and then return to book module, all pages lastly added were not saved. You can even try to change the format of the book: there's no way to not only recover pages lost but to see any pages added to the end if you leave the book module and back.

I never had this problem before and made quite recently a book in Lightroom 14.1 (end of November) and have made at leats 20 books printed by blurb using LR Classic Book Module. But the last one i was working on, was with 14.1.1 version and there's no way to finish.

I saved a back up of the Catalog with de error in Collection + Book Layout.

After the error you can only delete the collection for the book. Its is only unusable.

Thanks in advance.