So I was running my 2nd lap (I am after a long break from sports) and I was running slowly 6:50-7:10 min/km. Suddenly my screen went black and I got an information "battery saving" and a countdown from 30s . I didn't know what it was so I ignored it, but some time later when I checked my watch again I saw the main screen, and I had no data from that run. Please help me identify what went wrong.
To specify I didn't change any battery settings, I had 5 days of battery still after my run, during the run I was listening to music via Spotify. It's the first time it has happened to me, so if someone else got it, please tell me how to avoid it or can I recover the data from that run? After that run I did a Interval run session and it was all recorded properly, so I honestly don't know what might've caused it.