Board Game Arena

https://ru.boardgamearena.com/#!table?table=48299671
Why did this game end? I don't understand. Now one player can to end the game? Why?

If you click that link it even tells you why:

Game abandoned
The game has been abandoned because all players (with a positive clock) decided to do so, or because all players left the game.

--> essentially you ran over time and your opponent can then end the game, which he did. When you play on fast speed this can often happen.

OK, thank you.