When a Pin is not a Pin??

Hi all- first time posting but I was playing this game and thought I had the knight pinned but I was unable to capture the rook with the king

[Event "Online Game"]
[Site "Chess.com iPhone"]
[Date "2023.05.03"]
[Round "?"]
[White "Balambaras"]
[Black "Schnowzercise"]
[Result "0-1"]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
[WhiteElo "939"]
[BlackElo "962"]
[Termination "Schnowzercise won on time"]

1.d4 d5 2.c4 Nf6 3.Nc3 dxc4 4.e4 Nc6 5.d5 Nb4 6.Bxc4 e5 7.dxe6 Bxe6 8.Bxe6 fxe6 9.Qxd8+ Rxd8 10.Bg5 Nd3+ 11.Ke2 Be7 12.e5 Ng4 13.Bxe7 Kxe7 14.Nh3 Rhf8 15.f3 Ngxe5 16.Rad1 c5 17.b3 a6 18.f4 Nc6 19.Rxd3 Nd4+ 20.Ke3 Nf5+ 21.Kd2 Rxd3+ 22.Kxd3 b5 23.Re1 b4 24.Ne4 Rd8+ 25.Kc2 Nd4+ 26.Kb2 a5 27.Nxc5 Nb5 28.Kc2 Na3+ 29.Kc1 Rc8 30.Rxe6+ 30.Kf7 Ng5+ 31.Kg8 Re5 32.h6 {0-1}


Does anyone know why?

You cant capture the rook because you would be in check by the knight.

https://www.chess.com/forum/view/for-beginners/absolute-pinned-queen-can-still-be-a-defender-for-checkmate#comment-86507161

Yepp

Y

A pin is what you knock over when bowling and a tree is not a pin.