The bug has already been resolved - Fencer cancelled that illegal move! We must hope that it was only a rare exception and that the same problem won't arise in the future again ... :-)))
(hide) If you want to play a game with an opponent of a similar level, you can define a required BKR range for a new game invitation. Then nobody with a BKR outside this range will be able to see/accept it. (Katechka) (show all tips)