Cannot load cached AssetBundle. A file of the same name is already loaded from another AssetBundle.

hello..

I am loading gameobject from assets bundle on server. Code which i am using is here :

 IEnumerator Start () {
 
         string model  = PlayerPrefs.GetString("LoadModel" , "GoblinBundle");
         string url = "http://oceanstechnologies.com/service/emailcampaign/websites/tempr/unity/"+model;
         // Start a download of the given URL
         #if   UNITY_ANDROID && !UNITY_EDITOR
         url += ".android.unity3d";
         #elif UNITY_IPHONE  && !UNITY_EDITOR
         url += ".iphone.unity3d";
         #else
         url += ".unity3d";
         #endif
 
         www = WWW.LoadFromCacheOrDownload(url, 1);
         yield return www;
         
         //Debug.Log("Loaded ");
         
         if (www.error != null)
             throw new Exception("WWW download had an error: " + www.error);
         
         AssetBundle assetBundle = www.assetBundle;
         skull = Instantiate(assetBundle.mainAsset) as GameObject; // Instantiate(assetBundle.Load("AssetName"));
         skull.transform.position = new Vector3(0 , 0.0f , 15.0f)
         skull.gameObject.SetActive(false);
 
     }

I am getting my object loaded but on next scene i want same object to be loaded/use. when i write this code in next scene , i got this error.

So how can i use this same object in another scene .

Thanks..