Can someone explain why this is a repitition?

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syntex00

So I played a game and was somehow struggling to mate.
But then chess.comn decided for repitition draw, and I dont really get it.
Can someone clarify for me?

72.
Qd5
Kb6
73.
Kc4
Kc7
74.
Kc5
Kb8
75.
Qd6+
Kb7
76.
Qc6+
Kb8
77.
Qd6+
Kb7
78.
Kb5
Kc8
79.
Kc5
Kb7
Martin_Stahl
syntex00 wrote:

So I played a game and was somehow struggling to mate.
But then chess.comn decided for repitition draw, and I dont really get it.
Can someone clarify for me?

72.
Qd5
Kb6
73.
Kc4
Kc7
74.
Kc5
Kb8
75.
Qd6+
Kb7
76.
Qc6+
Kb8
77.
Qd6+
Kb7
78.
Kb5
Kc8
79.
Kc5
Kb7

After black's moves 75, 77, and 79 the exact same position is on the board and the same side to move. That is a triple repetition of position and automatically drawn in live games here.

https://support.chess.com/article/1042-i-got-a-draw-by-repetition-how-did-that-happen