Which part are you stuck in? We recommend playing the game with sound on. Every pipe that is rotated in the correct position will give a clicking sound. Hope this help
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The top row/button of the pipe is already in the correct position from the cutscene. So you don’t have to worry about the top row. You can switch between the 2nd row and the 3rd row by accessing the control box on the right side of the room. Be careful when switching between rows, you might notice something unusual mechanism. You can confirm the puzzle is solved by interacting bathroom’s wastafel. Hope this help