Cannot create mesh from code,Cannot use Script to Generate 2d mesh

Despite following tutorials and rewriting code again and again I just cannot get this 2d mesh to show up in the game: using System.Collections; using System.Collections.Generic; using UnityEngine;

[RequireComponent(typeof(MeshFilter))]

public class SandGenerator : MonoBehaviour { Mesh mesh; public Vector3[] vertices; public int[] triangles;

private void Start() { mesh = new Mesh(); GetComponent().mesh = mesh; CreateShape(); UpdateMesh(); }

 void CreateShape()   
   { 
       vertices = new Vector3[3];
         
         vertices[0] = new Vector3 (0,0,0);
         vertices[1] = new Vector3 (1,0,1);
         vertices[2] = new Vector3 (0,0,1);
         

         triangles = new int[3];
         triangles[0] = 0;
         triangles[1] =2;
         triangles[2] =1;

   }


 void UpdateMesh ()
 {
     mesh.Clear();

     mesh.vertices = vertices;
     mesh.triangles = triangles;
   }

},Despite following tutorials and re-writing the code again and again I just cannot get a simple mesh to appear. Any help would be great, what am I doing wrong? using System.Collections; using System.Collections.Generic; using UnityEngine;

[RequireComponent(typeof(MeshFilter))]

public class SandGenerator : MonoBehaviour { Mesh mesh; public Vector3[] vertices; public int[] triangles;

private void Start() { mesh = new Mesh(); GetComponent().mesh = mesh; CreateShape(); UpdateMesh(); }

 void CreateShape()   
   { 
       vertices = new Vector3[3];
         
         vertices[0] = new Vector3 (0,0,0);
         vertices[1] = new Vector3 (1,0,1);
         vertices[2] = new Vector3 (0,0,1);
         

         triangles = new int[3];
         triangles[0] = 0;
         triangles[1] =2;
         triangles[2] =1;

   }


 void UpdateMesh ()
 {
     mesh.Clear();

     mesh.vertices = vertices;
     mesh.triangles = triangles;
   }

}