Send JSONArray Data to MySQL

Question

I have a JSONArray, retrieving from Android local SQLite database, which I want to send to MySQL database. The JSONArray structure is as following

[
    {
        "value1": "1518518041",
        "value2": "90.390342",
        "value3": "23.7758309"
    },
    {
        "value1": "1518518071",
        "value2": "90.3903512",
        "value3": "23.7758192"
    },
    {
        "value1": "1518518200",
        "value2": "90.390342",
        "value3": "23.7758309"
    },
    ....
]

Now I am trying to send the data to MySQL using Volley JsonArrayRequest here is the code

JSONArray jsonArray  = db.getResults();
RequestQueue queue = Volley.newRequestQueue(this);
JsonArrayRequest sendSqliteData = new JsonArrayRequest(Request.Method.POST, URL, jsonArray,
        new Response.Listener<JSONArray>(){
            @Override
            public void onResponse(JSONArray jsonArray) {
                Toast.makeText(this, "Success", Toast.LENGTH_LONG).show();
            }
        },
        new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError volleyError) {
                Toast.makeText(this, volleyError.getMessage().toString(), Toast.LENGTH_LONG).show();
            }
        }) {
    @Override
    protected Map<String, String> getParams() throws AuthFailureError {
        HashMap<String, String> params = new HashMap<>();
        try {
            params.put("value1", jsonArray.getString("value1"));
            params.put("value2", jsonArray.getString("value2"));
            params.put("value3", jsonArray.getString("value3"));                
        } catch (JSONException e) {
            e.printStackTrace();
        }
        return params;
    }
};;
queue.add(sendSqliteData);

Here is the php script

<?php
// connect to database
$link = mysqli_connect($hostname, $username, $password);
mysqli_select_db($link, "myDatabase");

// get the JSONArray the app sends
$contents = file_get_contents('php://input');

$jsonArray = json_decode($contents, true);
$jsonCount = count($jsonArray);

for ($i = 0; $i < $jsonCount; $i++) {
    $item = $jsonArray[$i];
    $value1 = utf8_decode($item['value1']);
    $value2 = utf8_decode($item['value2']);
    $value3 = utf8_decode($item['value3']);


    $query = "INSERT INTO dataTable VALUES('$value1', '$value2', '$value3')";
    mysqli_query($link, $query);
}

Where I am doing wrong? Why the data is not writing in MySQL table?

EDIT: The problem I am getting in the Try/Catch block.

@Override
    protected Map<String, String> getParams() throws AuthFailureError {
        HashMap<String, String> params = new HashMap<>();
        try {
            params.put("value1", jsonArray.getString("value1"));
            params.put("value2", jsonArray.getString("value2"));
            params.put("value3", jsonArray.getString("value3"));                
        } catch (JSONException e) {
            e.printStackTrace();
        }
        return params;
    }

In the Try/Catch block I am retrieving String from the jsonArray whereas I am requesting volley to make a JsonArray post. My problem is I have data already in jsonArray variable in the format given upper JSON sample. How can I send that JSON to server using PHP. I am trying with this code but its not working. Please suggest me or edit the given code to do it properly.