DietersMistakesIn2022/Solution19

Moves 36 to 36  

Black should respond locally or, less obvious, pressure at c first.

Moves 36 to 36  

is a mistake. White lives locally and can ignore to play and destroy the lower side which was Black's main source of potential points.

(the diagrams below repeat what is essentially said at Four Die But Six Live)

Life and death @  

Black can't kill, at best take 2 stones in gote

Failure: surrounding to next force into small life but giving up consecutive sente.