I have played as white in this 9x9 game: https://online-go.com/game/16296789
Obviously my opponent tried to invade into the upper territory. However, he stopped this and passed and so did I. I considered the upper territory to be mine as long as my opponent does not proceed the invasion.
So, once the selection of dead stones was displayed, I marked the black invader as dead and pressed “accept”.
After that my opponent did something and the game ended scoring the entire upper group as dead.
There might be a way to kill it (too complicated to predict for a player of my rank) but as long as that did not happen and both players pass, it should be white’s, shouldn’t it?
Furthermore, I would expect the game to continue if there is a conflicting understanding of a group’s status. Instead I just died and the game ended.
Can someone explain why?