Drone falls out of sky??

[dronegirl]

Hi, I have a parrot bebop 2 power, and it falls out of the sky. Three times since I've had it it's fallen out of the sky for no reason. Today I was flying it, the battery was 30%, maybe 30 meters high, then it sends error message 'low battery alert' I tried to bring it down but it started falling and it crashed, it was ok, the cover over the usb port broke off, and the battery had fallen out, but other than that it seems ok, it still flies. The controller had plenty of battery power, it was only about 60-80 meters away from me, it was doing fine, then it just falls. I was flying it in an open field, it didn't crash into anything. I can't figure out why this happens, I just wouldn't want it to fall if I'm flying it over water or something. I looked at the video, and it just starts wobbling a lot, then it looks like the blades are in front of the camera, then it just stops.

 

[mikeexplorer]

One of the cells in the battery are probably bad and loses voltage quickly. I have had this happen but it did not fall, it dropped to 2% and the drone autolanded. Launch it and just let it hover, I am betting when the battery gets to 30%, watch it close, it probably drops like a rock and that causes the drone to shut off