Maybe you or your opponnent unchecked the box "autowin on time" in settings.
Will they remain there forever then?
I once had this setting turned off, the games remained until the opponent moved or I turned it on.
If you have that option turned on, you can go into the game and click "Claim win on time" below the chat box to end the game.
Unless the game has fewer than 2(? I think that's the right number) of moves in it. If that is the case, the game must be aborted.
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