I was sitting in my driveway with the a/c on for a couple minutes before going out. My battery was 68%, and I was in park. Suddenly it chimed with the message "Pull over immediately, unable to drive." It was no longer in park, so I restarted it. I drove down the street a bit and it seemed fine but I'm worried this will happen while I'm driving. I contacted roadside assistance and they told me they remotely checked my car and it's fine. Any idea why this happened and if I should be worried?