I flew on a Sunday only three meters high to take some photos when the drone lost the signal and the control too for a few seconds when got back the control and I was able to land it off, I found very strange the procedure of the aircraft; On the same day I flew and everything went well! But the following week I did a 5-meter-high flight just for photos when the drone went up alone and it was out of control going from one side to another! I could not do anything! It just stopped because hit at a  wall and fell off on a balcony! If not I would have missed the drone!!! There was a small crack on the bottom wing! I used only the radio control RC; because I  would fly only a few meters high! I'm a cautious pilot, I always do a pre-flight checklist! I follow all the rules and check if the firmware is updated every time! I haven’t  flown since the accident; because I do not want to take the risk again! I am disappointed with the product, expected more quality in the safety issue! And even the risk of the aircraft crashing into a person and causing serious damage! I have already connected the product and it indicates everything is updated and normal! Can someone give an explanation?! Tks in advance!!!

  

Hello and good day. I am sorry to know what happened to your previous flight with your DJI Spark. This is not the experience we want you to have with your DJI Spark. Since this issue happened please contact DJI Support at https://www.dji.com/support for us to help you further regarding this matter. Thank you.

Hi,
I would try a recalibration well away from any electrical or metallic structures.  As I recall I had a very similar situation when my spark was new after just a couple of flights. It never happened since.
Good luck.
S.

The same thing happened to me but when it lost connection to the phone and RC, it just rose up and was returning to home. It reconnected and I took control of it because it was going to land in a tree. I never tried it again because it is winter here and too cold to fly with -21C but I hope it will not do that again. I was flying low as well to take picture of the house, like 5 or 6 meter high.