3D FlipBook - Fonts not loading in rendered document

The fonts in the in file are not loading correctly in the flipbook. In every other PDF viewer (desktop software) I have tried such as Acrobat, native OSx preview, chrome browser, Word etc the document fonts are displayed correctly. Its not all fonts either.

https://i.ibb.co/mGxhhHB/screenshot.png

and PDF https://www.transfernow.net/dl/20230726terwDbmI - on a free transfer site ( valid 7 days )

This file is made monthly and last 2 months has failed. The producer advises no change BUT when I look at the file I do see this information change.

When I viewed the source.

Here is the current PDF (linked above)

Creator CCI Europe (PDFGenerator Release CUEPrint3.26.0.2z)
CreationDate    D:20230724181512+08'00'
Producer    Artifex Ghostscript 10.01.1
ModDate D:20230724181512+08'00'

Here is an older one

Creator CCI Europe (PDFGenerator Release CUEPrint3.26.0.2f)
CreationDate    D:20230217170218+08'00'
Producer    Artifex Ghostscript 9.55.0
ModDate D:20230217170218+08'00'

So the ghost script version has changed?