AppleCarplay not working

Very strange issue. About 2 wks ago my apple Carplay stopped working in my 2021 Kia Sportage. When plugging in my iphone XS Max to my USB port, a message continues to flash on and on "Searching for USB connection. I took the car to the dealer thinking there was something wrong with the USB port. They replied later that there was nothing wrong. I have been trying different things to get it working, 3 different cables, etc. My wife's iphone 8 works to bring up Apple Play in my car, the dealer repair tech put his iphone in my usb slot and it worked. Mine doesn't. I called Apple help and they went through several steps with me, including "forgetting" the connection between my car and apple play and then reinstalling apple play. It still doesnt work. I'm now installing IOS 15.1 which several people suggested I try. I have an appt with the genius bar this evening but not sure they can help. Wonder if anyone else has this issue???