Books keeps resetting theme to original

Every time I open my book app on my 15 pro max, it resets my theme in front of my eyes, within seconds of opening my book, to Original theme. I prefer to have it on Quiet, which it starts on, before switching itself. It’s very annoying because I then have to go back to bookmarks to find the page I was on which was thrown out of whack with the theme reset.

Does anyone else have this happen or know how to stop it?