Why is one side of my mesh cube correct, but the other side isn't?

I am trying to make a cube using a script generated mesh, but one side is half correct while the other side is not. The corresponding sides are top and bottom, but I rotated the square.

Here is my code:

 void Start()
     {
         mesh = new Mesh();
 
         mesh.vertices = GenerateVertices();
         mesh.triangles = GenerateTriangles();
 
         mesh.RecalculateNormals();
         mesh.RecalculateBounds();
         mesh.RecalculateTangents();
             
         meshFilter = this.gameObject.AddComponent<MeshFilter>();
         meshFilter.mesh = mesh;
 
         meshCollider.sharedMesh = this.mesh;
 
       
     }
 
  public Vector3[] GenerateVertices(float up = 0f)
     {
         return new Vector3[]
         {
             //bottom
             new Vector3(-1, 0 - up, 1),
             new Vector3(1, 0 -up, 1),
             new Vector3(1, 0 - up, -1),
             new Vector3(-1, 0 - up, -1),
             new Vector3(0, 0 - up, 0),
             new Vector3(0, 0 - up, -1),
             new Vector3(0, 0 - up, 1),
             new Vector3(-1, 0 - up, 0),
             new Vector3(1, 0 - up, 0),
 
             //top
            new Vector3(-1, 2 - up, 1),
             new Vector3(1, 2 -up, 1),
             new Vector3(1, 2 - up, -1),
             new Vector3(-1, 2 - up, -1),
             new Vector3(0, 2 - up, 0),
             new Vector3(0, 2 - up, -1),
             new Vector3(0, 2 - up, 1),
             new Vector3(-1, 2 - up, 0),
             new Vector3(1, 0- up, 0),
           
             
 
 
             //left
             new Vector3(-1, 0 - up, 1),
             new Vector3(-1, 0 - up, -1),
             new Vector3(-1, 2 + up, 1),
             new Vector3(-1, 2 + up, -1),
             new Vector3(0, 2 + up, -1),
             new Vector3(0, 2 + up, 1),
             new Vector3(0, 0 - up, -1),
             new Vector3(0, 0 - up, 1),
             new Vector3(0, 1 - up, 0),
 
             //right
             new Vector3(1, 0 - up, 1),
             new Vector3(1, 0 - up, -1),
             new Vector3(1, 2 + up, 1),
             new Vector3(1, 2 + up, -1),
              new Vector3(1, 0 - up, 1),
             new Vector3(1, 0 - up, -1),
             new Vector3(1, 2 + up, 1),
             new Vector3(1, 2 + up, -1),
               new Vector3(1, 2 + up, -1),
 
             //front
             new Vector3(1, 0 - up, -1),
             new Vector3(-1, 0 - up, -1),
             new Vector3(1, 2 + up, -1),
             new Vector3(-1, 2 + up, -1),
             new Vector3(1, 0 - up, -1),
             new Vector3(-1, 0 - up, -1),
             new Vector3(1, 2 + up, -1),
             new Vector3(-1, 2 + up, -1),
             new Vector3(-1, 2 + up, -1),
 
             //back
             new Vector3(-1, 0 - up, 1),
             new Vector3(1, 0 - up, 1),
             new Vector3(-1, 2 + up, 1),
             new Vector3(1, 2 + up, 1),
             new Vector3(-1, 0 - up, 1),
             new Vector3(1, 0 - up, 1),
             new Vector3(-1, 2 + up, 1),
             new Vector3(1, 2 + up, 1),
              new Vector3(1, 2 + up, 1),
         };
 
 
     }
 
     public int[] GenerateTriangles()
     {
         return new int[]
         {
            //top
            //top right
             1, 6, 4,
             8, 1, 4,
             
             
 
 
             7, 4, 6,
             0, 7, 6,
 
 
             //bottom left
             5, 4, 7,
             3, 5, 7,
 
             //top left
             8, 4, 5,
             2, 8, 5,
 
 
             
             //left
             //left
             9, 10, 11,
             8, 10, 9,
 
             //right
             12, 13, 15,
             14, 12, 15,
 
             //forward/back
             16, 17, 19,
             18, 16, 19,
             20, 21, 23,
             22, 20, 23
 
         };
     }