Hello ck-13,
Welcome to Apple Support Communities!
We want to resolve the issue so you can use CarPlay to hear your messages.
Use the steps here to enable this option:
"Announce incoming text messages with CarPlay
Use CarPlay to have Siri automatically read your incoming text messages and listen for your response.
- On your iPhone, go to Settings
> Siri & Search > Announce Notifications, then turn on Announce Notifications. - Tap CarPlay, then choose any of the following:
- Announce New Messages: CarPlay starts your drive with Announce Messages active and reads your incoming text messages aloud.
- Silence New Messages: CarPlay starts your drive with Announce Messages silenced and doesn’t read incoming text messages automatically.
- Remember Previous Setting: CarPlay remembers whether Announce Messages were active or silenced from the previous drive."
If the issue continues, update your device to the latest version here: Update your iPhone or iPad - Apple Support
"Update your iPhone or iPad wirelessly
- Back up your device using iCloud or your computer.
- Plug your device into power and connect to the internet with Wi-Fi.
- Go to Settings > General, then tap Software Update.
- If you see more than one software update option available, choose the one that you want to install.
- Tap Install Now. If you see Download and Install instead, tap it to download the update, enter your passcode, then tap Install Now. If you don't know your passcode, learn what to do."
We hope this helps to get the software working as expected and announcing your messages via CarPlay again.
Cheers!