Some files not readable in dark mode on Kobo Clara BW

Hi, when I lend books from my public libary, I have to download the .ascm from https://ebook.yourcloudlibrary.com/

Next I convert the .acsm file to epub with Adobe Digital Editions 4.5 and then transfer that file to my Kobo Clara BW.
The problem is that some of these books are not readable in Dark Mode, but they are readable in White Mode.

See attached screenshots.

I don't know what is the cause?