Computer resigned strangly

Hello, just a few minutes ago played a game against Stockfish lvl 7, and he resigned in totally draw position, after, as i think, 50 moves without taking (I'm talking about 50 moves rule, why didn't lichess claimed a draw?). Can anyone somehow explain it?
Here's the game: lichess.org/s0mjKUzu

The computer auto resigns at move 151.

Why is it working so? Does it make sense?

Why?

I've tryed to play a game with 151 moves and it also resigned.

look at the game bellow