Its something with AA. Mine stopped the other day too and I've tried my Note, my sons S10+ and my Pixel 4XL. None work and there are forums out there and reviews that show this is a growing problem.
My note 10 + 5g works fine with no issues with AA on my 2020 Koleos with a usb cable.
It won't work on wireless aa though as I think the car headset needs WiFi 5g to work with aa wireless. Has anyone got it working with wireless auto.