مشکل در اسکرول سریع ریسایکرویو

سلام 

هنگامی که ریسایکلرویو اسکرول سریع میشه ایتم ها جابجا میشه. ترتیب دریافت هم به این صورت است که لیست بی پایان هست که 12 تا 12 از سرور میگیره.

مشکل از کجاس؟

با تشکر

زمانی که اسکرول میشه

public  class home_agahi3_server  extends AsyncTask<String,Void,String> {

    private Context c;
    private Activity ac;

    private String state_id;
    private String lim;
    private RecyclerView rec;
    AgahiRecyclerAdapter adp;


    public home_agahi3_server(Context c,Activity ac,String lim,AgahiRecyclerAdapter adp
    ){
        this.c=c;
        this.ac=ac;

        this.lim=lim;
        this.adp=adp;



    }


    @Override
    protected void onPreExecute() {
        super.onPreExecute();



        lay2.setVisibility(View.VISIBLE);


    }

    @Override
    protected String doInBackground(String... strings) {


            try {
                String data = URLEncoder.encode("get_post", "UTF-8") + "=" + URLEncoder.encode("true", "UTF-8");
                //  data+="&"+ URLEncoder.encode("state_id", "UTF-8")+"="+URLEncoder.encode(state_id,"UTF-8");
                data += "&" + URLEncoder.encode("lim", "UTF-8") + "=" + URLEncoder.encode(lim, "UTF-8");

             //Thread.sleep(10);
             //  SystemClock.sleep(1000);


                //
                URL url = new URL(MainActivity.url + "post.php");
                URLConnection connect = url.openConnection();
                HttpURLConnection urlc = (HttpURLConnection) url.openConnection();
                urlc.setConnectTimeout(3000);
                urlc.connect();

                errorMessage = urlc.getResponseCode() == 200 ? "Successful Connection" : "Internet Error";
                if (urlc.getResponseCode() == 200) {

                    connect.setDoOutput(true);
                    OutputStreamWriter wr = new OutputStreamWriter(connect.getOutputStream());
                    wr.write(data);
                    wr.flush();
                    wr.close();

                    //
                    InputStreamReader in = new InputStreamReader(connect.getInputStream());
                    BufferedReader reader = new BufferedReader(in);
                    String line = "";
                    StringBuilder sb = new StringBuilder();
                    while ((line = reader.readLine()) != null) {
                        sb.append(line);

                    }
                    return sb.toString();
                }


            } catch (SocketTimeoutException e) {
                errorMessage = "Connection Error1";
                return "err1";

            } catch (MalformedURLException e) {
                errorMessage = "Connection Error2";
                return "err1";

            } catch (IOException e) {
                errorMessage = "Connection Error3";
                return "err1";

            }

        return "";


    }

    @Override
    protected void onPostExecute(String s) {
        super.onPostExecute(s);
       // lay2.setVisibility(View.GONE);
      //  lay2.setBackgroundResource(R.drawable.bg_cadr_around);

        if(s.equals("err1")||s.equals("")){

            final android.app.AlertDialog OptionDialog = new android.app.AlertDialog.Builder(getActivity()).create();
            LayoutInflater factory = LayoutInflater.from(getActivity());
            final View f = factory.inflate(R.layout.row_connect, null);
            OptionDialog.setView(f);
            MainActivity.K= Typeface.createFromAsset(getActivity().getAssets(), "fonts/k.ttf");
            MainActivity.T=Typeface.createFromAsset(getActivity().getAssets(),"fonts/t.ttf");
            TextView txt_1= (TextView) f.findViewById(R.id.connect_txt1);
            TextView txt_2= (TextView) f.findViewById(R.id.connect_txt2);
            OptionDialog.setCancelable(false);
            txt_1.setTypeface(MainActivity.K);
            txt_2.setTypeface(MainActivity.K);
            txt_1.setText("عدم دسترسی به اینترنت ");

            txt_2.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    OptionDialog.dismiss();


                    mTask = new home_agahi3_server(getActivity().getApplicationContext(), getActivity(),
                            limit + "", adapter
                    );
                    mTask.executeOnExecutor(mTask.THREAD_POOL_EXECUTOR, "");
                }
            });

            OptionDialog.show();


        }else {

            lay2.setVisibility(View.GONE);



            JSONArray arr = null;
            JSONObject ob = null;

            //Toast.makeText(c,scroll+"",Toast.LENGTH_SHORT).show();
            scroll = 0;
            try {
                arr = new JSONArray(s);
                for (int i = 0; i < arr.length(); i++) {

                    ob = arr.getJSONObject(i);

                    _name.add(ob.getString("title"));
                    _img.add(ob.getString("img"));
                    _price.add(ob.getString("price"));
                    _menu_order.add(ob.getString("order"));
                    _id.add(ob.getString("id"));

                    _time.add(ob.getString("time"));

                    /*_imgs.add(ob.getString("imgs"));

                    _color.add(ob.getString("color"));
                    _size.add(ob.getString("size"));
                    _shenas.add(ob.getString("shenas"));

                    _expire.add(ob.getString("expire"));
                    _visit_today.add(ob.getString("todayvisit"));
                    _visit_total.add(ob.getString("totalvisit"));
                    _mobile.add(ob.getString("mobile"));
                    _cat.add(ob.getString("cat"));
                    _user_id.add(ob.getString("user"));

                    _link.add(ob.getString("link"));*/


                }

                              // adapter.notifyItemRangeInserted(limit,_time.size());
                adapter.notifyDataSetChanged();




            } catch (Exception e) {
                //Toast.makeText(c,"errors in json",Toast.LENGTH_SHORT).show();
            }
        }

    }
}