I've noticed my Mavic 3 doesn't show accurate altitudes, much of the time. It is often 10 ft to 20 ft off the true altitude, based on comparing my height above the ground to known altitudes of object around my property, like certain tries, to top of my chimney, my windmill, things like that. I've seen it hover above the ground about 2 ft and the altitude shows it at 20 ft. I thought the vertical gps accuracy was only a couple of feet, and I've never had this issue with my Air 2. Any ideas on what is causing this, or any way to mitigate or correct? I'm worried about running Waypoints if the drone doesn't know it's actual altitude.