According to official chess rules, this 
is a draw as white hasnt got the sufficient material to win, but black got flagged, how does lichess put this through as a loss for black
According to official chess rules, this 
is a draw as white hasnt got the sufficient material to win, but black got flagged, how does lichess put this through as a loss for black
"According to official chess rules"
6.9 Except where one of Articles 5.1.1, 5.1.2, 5.2.1, 5.2.2, 5.2.3 applies, if a player does not complete the prescribed number of moves in the allotted time, the game is lost by that player. However, the game is drawn if the position is such that the opponent cannot checkmate the player’s king by any possible series of legal moves.
In this case there exists a series of legal moves that leads to checkmate, so you duly lost on time.
If you dislike that, then play with increment.
"According to official chess rules"
6.9 Except where one of Articles 5.1.1, 5.1.2, 5.2.1, 5.2.2, 5.2.3 applies, if a player does not complete the prescribed number of moves in the allotted time, the game is lost by that player. However, the game is drawn if the position is such that the opponent cannot checkmate the player’s king by any possible series of legal moves.
In this case there exists a series of legal moves that leads to checkmate, so you duly lost on time.
If you dislike that, then play with increment.
Insufficient material means there is no material left on the board that allows for a checkmate to happen.
Here is one possible checkmate: https://lichess.org/editor/6nk/1p3N2/4p1K1/p7/8/3r4/8/8_b_-_-_1_1?color=black
So you just lost on time.
Insufficient material means there is no material left on the board that allows for a checkmate to happen.
Here is one possible checkmate: https://lichess.org/editor/6nk/1p3N2/4p1K1/p7/8/3r4/8/8_b_-_-_1_1?color=black
So you just lost on time.