Wrong treatment of the game result

There was no way black could win, however the system gave them a victory by time.

[Variant "From Position"]
[FEN "8/6b1/6k1/6P1/4K3/8/8/8 w - - 7 66"]

66. Kd3 Kf7 67. g6+ Ke7 68. Kc2 Bf6 69. g7 Kd6 70. g8=B Kc5 71. Kb1 Kb4 72. Ba2 Be7 73. Ka1 Ka3 74. Bb1 Bf6#
Black can win if white underpromotes to bishop, then brings his king and bishop to the corner and gets mated

funny but that's ok