iPhone Pro Max 15 won't connect wirelessly to Carplay

I received my new iPhone Pro Max 15 and connected it wirelessly to my Apple Carplay. 4 days later it stopped connecting wirelessly but will connect with the USB wired connection. I have a 2023 Porsche Cayenne and never had a problem with wireless connection with my previous iphone. I researched and followed all the steps - deleting my phone from the car and the car from my phone etc. I can see the phone (it connects wirelessly to the car) but Apple Carplay will not activate unless the USB is connected. I had the dealership "expert" call me and walk me through a 20 minute process, even rebooting the car computer, and no success. I took the car to the dealer and spent another 20 minutes while they tried to get it to connect. Their final answer was that it was a problem with the new phone software. Then why did it work for 4 days? And I updated the software immediately upon getting the phone so there is no software change. It is not hopeless as I can connect with the USB but it is frustrating. I am a Realtor and I am constantly in and out of my car and it would be nice if it just connected to carplay without plugging in. Any suggestions?