Hello sbennet5,
Thank you for reaching out in Apple Support Communities. Just to be sure, we recommend to ensure that your iPhone has the latest version of iOS 16.5.1. Having the latest iOS version helps provide software improvements that may help. You can check by going to Settings > General > Software Update.
Then, you'll want to ensure that your 2021 Alfa Romeo has the latest firmware installed. If you're unsure, you'll need to contact them and see if you have the latest firmware version installed.
If the iPhone and the vehicle are up to date, we recommend to restart your iPhone and test to see if the notification for read messages continue to appear. This is a step that may help. Here's how to properly restart an iPhone:
How to restart your iPhone X, 11, 12, 13, or later
1. Press and hold either volume button and the side button until the power-off slider appears.

2. Drag the slider, then wait 30 seconds for your device to turn off. If your device is frozen or unresponsive, force restart your device.
3. To turn your device back on, press and hold the side button (on the right side of your iPhone) until you see the Apple logo.
These steps are outlined in this helpful article: Restart your iPhone - Apple Support
We look forward to hearing back from you with an update.
Kind regards.