Terrain edit on multiplayer

i have a terrain editor that can raise the terrain on mouse click. however i tried this on a multiplayer network, and i can only see the terrain change on the host i added networkview on the terrain, so i don't know what's wrong this is the script that i have attached to the terrain using UnityEngine; using System.Collections;

 public class TerrainEdit : MonoBehaviour
 {
     public Terrain myTerrain;
     int xResolution;
     int zResolution;
     float[,] heights;
     
     void Start()
     {
         xResolution = myTerrain.terrainData.heightmapWidth;
         zResolution = myTerrain.terrainData.heightmapHeight;
         heights = myTerrain.terrainData.GetHeights(0,0,xResolution,zResolution);
     }
     
     void Update()
     {
 
         if(Input.GetMouseButton(1))
         {
             RaycastHit hit;
             Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
             if(Physics.Raycast(ray, out hit))
             {
                 raiseTerrain(hit.point);
                 myTerrain.Flush();
             }
         }
     }
 
     private void raiseTerrain(Vector3 point)
     {
         int terX =(int)((point.x / myTerrain.terrainData.size.x) * xResolution);
         int terZ =(int)((point.z / myTerrain.terrainData.size.z) * zResolution);
         float y = heights[terX,terZ];
         y += 0.0005f;
         if (y > 1)
                         y = 1;
         float[,] height = new float[1,1];
         height[0,0] = y;
         heights[terX,terZ] = y;
         myTerrain.terrainData.SetHeights(terX, terZ, height);
     }
 }