custom info window showing duplicate data from json android studio

Question

I'm really new to Android programming.

Why is my data all the same? I'm getting data from JSON and putting it in a custom info window. Why is it all duplicated, but the markers are not?

I can't send pictures because it's my first time here asking questions.

This is my Adapter class

Adapter Class

public class MarkerInfoWindowAdapter implements GoogleMap.InfoWindowAdapter {
private Context context;
private TextView tvnama, tvalamat, tvkursi, tvmeja, tvstop, tvlain, tvket;
public static String stonama, stoalamat, kursisto, mejasto, stopkontaksto, lainlainsto, keterangansto, id;
public MarkerInfoWindowAdapter(Context context){
    this.context = context.getApplicationContext();
}

@Override
public View getInfoWindow(Marker marker){
    return null;
}
@Override
public View getInfoContents(Marker marker){
    LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View v = inflater.inflate(R.layout.map_marker_info_window, null);
    tvnama = (TextView) v.findViewById(R.id.tv_namasto);
    tvalamat = (TextView) v.findViewById(R.id.tv_alamatsto);
    tvkursi = (TextView) v.findViewById(R.id.tv_kursisto);
    tvmeja = (TextView) v.findViewById(R.id.tv_mejasto);
    tvstop = (TextView) v.findViewById(R.id.tv_stopkontaksto);
    tvlain = (TextView) v.findViewById(R.id.tv_lainlainsto);
    tvket = (TextView) v.findViewById(R.id.tv_keterangansto);
    tvnama.setText("Nama STO: "+stonama);
    tvalamat.setText("Alamat STO: "+stoalamat);
    tvkursi.setText("Fasilitas Kursi: "+kursisto);
    tvmeja.setText("Fasilitas Meja: "+mejasto);
    tvstop.setText("Fasilitas Stop Kontak: "+stopkontaksto);
    tvlain.setText("Fasilitas Lain Lain: "+lainlainsto);
    tvket.setText("Keterangan: "+keterangansto);
    return v;
}
}

MapsActivity

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {

private GoogleMap mMap;
private String[] nama_sto, alamat_sto, kursi, meja, stop, lain, keterangan, id;
int numData;
LatLng latLng[];
Boolean markerD[];
private Double[] latitude, longitude;

private void getLokasi() {
    String url = "http://huracan97.site/api/GetSTO.php";
    JsonArrayRequest request = new JsonArrayRequest
            (Request.Method.GET, url, new Response.Listener<JSONArray>() {
                @Override
                public void onResponse(JSONArray response) {
                    numData = response.length();
                    Log.d("DEBUG_", "Parse JSON");
                    latLng = new LatLng[numData];
                    markerD = new Boolean[numData];
                    id = new String[numData];
                    nama_sto = new String[numData];
                    alamat_sto = new String[numData];
                    kursi = new String[numData];
                    meja = new String[numData];
                    stop = new String[numData];
                    lain = new String[numData];
                    keterangan = new String[numData];
                    latitude = new Double[numData];
                    longitude = new Double[numData];

                    for (int i = 0; i < numData; i++) {
                        try {
                            JSONObject data = response.getJSONObject(i);
                            id[i] = data.getString("id_sto");
                            latLng[i] = new LatLng(data.getDouble("latitude"),
                                    data.getDouble("longitude"));
                            nama_sto[i] = data.getString("nama_sto");
                            alamat_sto[i] = data.getString("alamat_sto");
                            kursi[i] = data.getString("fasilitas_kursi");
                            meja[i] = data.getString("fasilitas_meja");
                            stop[i] = data.getString("fasilitas_stopkontak");
                            lain[i] = data.getString("fasilitas_lainlain");
                            keterangan[i] = data.getString("keterangan");
                            latitude[i] = data.getDouble("latitude");
                            longitude[i] = data.getDouble("longitude");
                            MarkerInfoWindowAdapter.stonama = nama_sto[i];
                            MarkerInfoWindowAdapter.stoalamat = alamat_sto[i];
                            MarkerInfoWindowAdapter.kursisto = kursi[i];
                            MarkerInfoWindowAdapter.mejasto = meja[i];
                            MarkerInfoWindowAdapter.stopkontaksto = stop[i];
                            MarkerInfoWindowAdapter.lainlainsto = lain[i];
                            MarkerInfoWindowAdapter.keterangansto = keterangan[i];
                            markerD[i] = false;
                            mMap.addMarker(new MarkerOptions()
                                    .position(latLng[i])

                            );

                        } catch (JSONException je) {}

                        mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng[i], 15.5f));
                    }



                }