Sort points by face

Hello, I am a beginner in Grasshopper and Rhino. After making some changes to a simple volume, I’d like to sort the lines by face to perform other operations.

However, I don’t understand why I get good results when selecting one face with List Item, but it doesn’t work correctly when I use the collection of the four faces of the volume to apply the same method. I believe that I need to use Series, but I’m not sure how to do it. Could you help me understand and resolve this issue?