Yeah two solutions keep restarting your phone or download a beta version there has been reports that it hass solved the issue, so next update should fix the issue

Apple are aware two solutions at the moment, update your phone to the beta version or turn on and off your phone everytime after using car play it will work

Does downloading the beta visions affect the warranty and can i say it is a massive relief that im not the only one having this issue. 6 months now !!