The game ends when one of the players gets the 6 characters, thus winning 300 coins.
The game can end before that if any of the players resigns or fails to answer on time. In any of these two situations, the game will be considered to have been won by the other player regardless of the number of characters. The winner will only get the coins if they had played at least three rounds.You have the possibility to reject game requests. That will not affect any of the player’s statistics. The game will not be lost or won.