Thanks for replying chrispy1953,
We appreciate that additional info, it really helps! To clarify, were you previously able to see more than the 20 options listed? We ask because mentioned in Play music with CarPlay - Apple Support: "On some systems, Now Playing displays only a partial list of choices while you’re driving. To choose among options not in the list, select More at the bottom of the screen, or use Siri by pressing and holding the voice command button on your steering wheel."
If you were previously able to see more options, and you've confirmed your vehicle firmware is updated, please contact Apple directly for further investigation:
Apple Support
Have a great day and thanks for using the Apple Support Communities!