LIChess did not catch this checkmate.

Hi. In a game against gp6273, LIChess allowed this player to make a move. However, a mating position was obtained. The player resigned due to the fact that, I think, he or she couldn't find an escape square or intervening piece to block check.

If I'm wrong, please point out where this player could escape check. Thank you.

Black can play Kxg7, that white pawn is not protected.

poor Black (major oops)

Ouch, that hurts!