onLoadFinished called with wrong data even if loadInBackground returns correct data

I am making an app to display the movies list as shown in the screenshot.

The problem is that when I select the options menu top_rated option it reloads the correct data but the list returned to onLoadFinished contains the previous data with the new data after that.

How do I rectify this as I want only the new data to be in the list. I tried onLoaderReset but it is not called because the activity is not destroyed and I am not able to find any other way to dereference the old data or in other words first empty the old already fetched list and then replace it with a newly fetched list.

How to achieve the above..?

And there is one more thing, that whenever I go to any other activity and then return back the data shown is duplicated. I know that this might be a lifecycle issue and can be solved with some research but I can do that only if the first issue is resolved.

Here is the screenshot of the app:- UPDATE --> The actual problem was not in MainActivity.java but in the below file and hence the problem is solved now as mentioned in my answer.

Here is my JSONUtils.java function which I was calling in MainActivity.java:-

import com.example.trishantsharma.popularmovies.Movie;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.util.ArrayList;

public class JSONUtils {
private static ArrayList<String[]> movieTitleAndPosterList = new ArrayList<>();
//ALL CONSTANTS HERE
public static ArrayList<String[]> parseMovieJSON(String jsonReceived){
    //THE PROBLEM IS HERE AND HAS BEEN RECTIFIED IN THE ANSWER
    try {
        JSONObject movieObject = new JSONObject(jsonReceived);
        JSONArray allMoviesArray = movieObject.getJSONArray(RESULT_JSON_ARRAY_STRING);
        for (int i = 0; i < 19; i++) {
            JSONObject particularMovie = allMoviesArray.optJSONObject(i);
            String movieId = Integer.toString(particularMovie.optInt(ID_JSON_OBJECT_STRING));
            String moviePoster = particularMovie.optString(POSTER_JSON_OBJECT_STRING);
            String[] singleMovieTitleAndPosterArray = {movieId,moviePoster};
            movieTitleAndPosterList.add(singleMovieTitleAndPosterArray);
        }
        return movieTitleAndPosterList;
    } catch (JSONException e){
        e.printStackTrace();
    }
    return null;
}
}

Thanks.

Here is the answer I referenced to in my question:-

Here is my JSONUtils.java function which I was calling in MainActivity.java:-

public static ArrayList<String[]> parseMovieJSON(String jsonReceived){
    movieTitleAndPosterList.clear();
    try {
        JSONObject movieObject = new JSONObject(jsonReceived);
        JSONArray allMoviesArray = movieObject.getJSONArray(RESULT_JSON_ARRAY_STRING);
        for (int i = 0; i < 19; i++) {
            JSONObject particularMovie = allMoviesArray.optJSONObject(i);
            String movieId = Integer.toString(particularMovie.optInt(ID_JSON_OBJECT_STRING));
            String moviePoster = particularMovie.optString(POSTER_JSON_OBJECT_STRING);
            String[] singleMovieTitleAndPosterArray = {movieId,moviePoster};
            movieTitleAndPosterList.add(singleMovieTitleAndPosterArray);
        }
        return movieTitleAndPosterList;
    } catch (JSONException e){
        e.printStackTrace();
    }
    return null;
}

Since the ArrayList here was static therefore I had to clear it before adding new data.

Since, I was not clearing it the data was always getting appended to the list and hence the list returned to onLoadFinished had duplicated items.

Thanks @KavinRajuS for taking the time in helping me solve this query. Hence, the problem is now fixed and the app is working well.