Instantiated Tiles get positioned randomly on android devices

I'm trying to make a tower defense 2D for Android, as I make the map with the instantiated tiles on prefabs, it worked perfectly on UnityEditor but once I import it to Android the tiles went out of the camera bounds like this

I made my Map Tiles like this

 private void CreateLevel()
     {
         Tiles = new Dictionary<Point, TileScript> ();
 
         string[] mapData = ReadLevelText ();
 
         mapSize = new Point (mapData [0].ToCharArray ().Length, mapData.Length);
 
         int mapX = mapData [0].ToCharArray ().Length;
         int mapY = mapData.Length;
 
         Vector3 worldStart = Camera.main.ScreenToWorldPoint (new Vector3 (0, Screen.height));
         for (int y = 0; y < mapY; y++)
         {
             char[] newTiles = mapData [y].ToCharArray ();  
 
             for (int x = 0; x < mapX; x++)
             {
                 PlaceTile (newTiles[x].ToString(),x,y,worldStart);
             }
         }
         SpawnPortals ();
     }
 
     private void PlaceTile(string tileType, int x, int y, Vector3 worldStart)
     {
         int tileIndex = int.Parse (tileType); 
 
         TileScript newTile = Instantiate (tilePrefabs[tileIndex]).GetComponent<TileScript>();
 
         newTile.Setup (new Point (x, y), new Vector3 (worldStart.x + (TileSize * x),worldStart.y - (TileSize * y), 0), map);
 
         Tiles.Add (new Point (x, y), newTile);
     }

I wonder if anyone has solution on this, I tried any way that I could do but the instantiated tiles(prefabs) seems to stuck at upper screen like the picture...