I started playing on friday evening at level 19. 

3 hours later I was about lvl 25 or 26, finished the 2 last dungeons of the story mode that I had not clear yet.

Then got disconnected, re launched the game and found my character back to lvl 19, lost the uniques I looted and that helped me pass the last dungeon.

Like I didn't play the whole night at all.

No internet disconnection whatsoever, was on discord the whole time.

Please help