Unity Nested FOR loops Bug

Question

I'm writing a script to randomly generate a maze, and I can't even get it off the ground, rip. I've written fractal generators so I'm no stranger to nested FOR loops. FOR x{ FOR y }
I'm using my same old tricks to generate the maze. To initialize it, I set the boundary of the Maze (NESW sides) to be walls like so:

// Create
List<Room> row = new List<Room>();
for(int i=0; i<width; i++)  // Columns (X-axis)
{   row.Clear();
    for(int j=0; j<depth; j++){ // Rows (Z-axis)
        row.Add(new Room(i, yOffset, j));

        if(i==width-1){ Debug.Log("SetE: i "+i+", j "+j);
        row[j].setE(-1); }
        if(i==0){ Debug.Log("SetW: i "+i+", j "+j);
        row[j].setW(-1); }
    }
    row[width-1].setN(-1);
    row[0].setS(-1);
    rooms.Add(row);
}
// Instantiate
for(int i=0; i<width; i++) for(int j=0; j<depth; j++)
{   // Room
    Instantiate(roomGO, new Vector3(i + transform.position.x,
                           yOffset, j + transform.position.z), transform.rotation);
    // North Side
    Instantiate(getWall(rooms[i][j],0), new Vector3(i + transform.position.x,
                                           yOffset, j + transform.position.z + .75f), transform.rotation);
    // East Side
    Instantiate(getWall(rooms[i][j],1), new Vector3(i + transform.position.x + .75f,
                                           yOffset, j + transform.position.z), transform.rotation);
    // South Side
    Instantiate(getWall(rooms[i][j],2), new Vector3(i + transform.position.x,
                                           yOffset, j + transform.position.z - .75f), transform.rotation);
    // West Side
    Instantiate(getWall(rooms[i][j],3), new Vector3(i + transform.position.x - .75f,
                                           yOffset, j + transform.position.z), transform.rotation);
}

My problem is here (*I think), Lines 7 to 10:

if(i==width-1){ Debug.Log("SetE: i "+i+", j "+j);
    row[j].setE(-1); }
if(i==0){ Debug.Log("SetW: i "+i+", j "+j);
    row[j].setW(-1); }

The positions are correct. I have no problems with the North and South sides.
The Western walls are not Instantiating. But the Eastern walls are Instantiating on every single row?
I'm trying to set all the West and East walls of the rooms with Coords (x=0/x=Width, z). The Debug.Log lines are printing the expected coordinates.
Question
Why aren't the Eastern and Western walls Instantiating properly? What is a better way to set the walls of my Maze?

Answer 1

Simple fix, the bug is not in lines 7 to 10 like I thought. Rather, because I'm adding the same instance of the List row, Clearing it, and adding it repeatedly, the rows get a little buggy. My fault for not seeing this.

Instead of rooms.Add(row), I should have been using rooms.Add(new List<Room>(row)). This way, when I dump row, I still have the data stored in rooms.

Special thanks to @DMGregory and @Pikalek