I don't think it is normal for your drone to fall out of the air. My drone does get hot on hot days but not hot enough to fall out of the sky. And not hot enough of the battery to fall out of the drone or disconnect somehow. I always make sure they are snug in there and latched before taking off every time as part of the pre flight check list. I don't think there is a design flaw in the
Air2S as I have not noticed any issues in any of my other Mavic drones either. There might be something wrong with your drone in general and it may need to go back to DJI for troubleshooting. Like I said I have flown in 90 degree days many days, flying on 8 batteries in high humidity days. So I don't what is wrong with your drone. Does it run hot? Yes it runs hot, and I monitor the temperature of the battery while I fly it. And it really stays cool enough to stay safe.