I start Google Maps Navigation using voice, e.g. "OK Google, navigate to the hospital." Navigation starts and navigates me there. Once I have arrived, I exit Navigation by pressing the return button several times until I reach the Home screen. After a couple of seconds, Navigation restarts itself. I have to again press the return button several times to finally end it. This only happens with voice activation. If I start Navigation by another method, e.g. from my Contacts, it doesn't auto-restart. This problem has been happening for a long time. Do you have any idea how to solve this issue? Nexus 5, stock unrooted, Android 6.0.1.