CarPlay STILL not working after three updates to iOS 18+++?

It's a documented problem that many have experienced. The only variable that changed is the phone update, and I've seen MANY people with the same complaint. It is a pretty new iphone (16 pro max) that works flawlessly in general and did work flawlessly with my also relatively new car right up until the morning I woke up to the first 18 update. The car's firmware was and still is up to date; VPN is not turned on with the phone. Every time there is a new update since 18 began, parts of CarPlay work, and others don't. It is activated immediately by saying Hey Siri, but the glowing frame then does nothing. If I tell it to message, it pulls up the person's name on screen with the message icon, but won't go any further. If I say to call, it does nothing but glow. The latest iteration seems to have added some functionality back in--I can now ask for a song on Spotify or ask for directions; both take about 30-60 seconds whereas they used to be very quick, a few seconds. The screen never shows what I'm asking in any way (other than bringing up a messaging icon); it never responds with any speech. The screen glows and then eventually stops. I've checked all of the settings, reconnected and disconnected via Bluetooth/ unpaired on both ends, re-paired, manually powered down and turned the phone back on. Siri still works on my phone except for these issues with CarPlay. I have watched every video I can find on this problem (as it IS happening with iOS 18) and still, no dice. I do these steps every time there is an updated. Some people seem to have luck unpairing and re-pairing, others have to do it every time they turn on their car, and still others can't get it to work at all. Thank you for the suggestions--hopefully they will help the next person who hasn't reached the point yet of having exhausted those options.