Using 'npm run' (per the readme file) returns an error but using 'npm start' (per the video) begins the process.

It only turns a single page of the Kindle book that is open (I am leaving the 'number of pages' field blank for unlimited ), then returns a pdf in the 'book' folder that is a single page screenshot of my wallpaper, nothing from the Kindle.

Any idea what I am missing?