Waypoints and Tracks data lost after smartphone powered off

I was saving my track (typing name) just when device powered off on 0% battery. Once recharged and switched on, I don't have any Waypoints and Tracks - all are gone. Offline maps and settings are still available.

Backup shows 0 files even when I backup data regularly. When I try to change main folder, setting does not work - endless loading message. I can't find any Locus related data in file directory. It's all strange, in the past I was always able to find my data, even unfinished tracks when device went off.