Log shows response like this:

I sent a PHP array using JSON encode from server which outputs this:

How can I get my array from the unexpected response code? The array is sent as JSON encode.
PHP:
<?php
require "conn.php"; 
class person {
        public $id;
        public $age;
        public $name;
        public $lat;
        public $longi;
        public $email;
        public $image;
        public $number;
    }
$bloodgroup = $_POST["bloodgroup"];
$sql = "Select * from UserDetails where bloodgroup = '$bloodgroup'";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
$donorsArray = array();
    while($row = $result->fetch_assoc()) {
        $donor = new person;
        $donor->id = $row["ID"];
        $donor->age = $row["age"];
        $donor->name = $row["Name"];
        $donor->lat = $row["lat"];
        $donor->longi = $row["longi"];
        $donor->email = $row["email"];
        $donor->image = $row["image"];
        $donor->number = $row["number"]; 
        $donorsArray[] = $donor;
    }
} else {
}
echo json_encode(array_values($donorsArray));
?>
Java:
OkHttpClient client = new OkHttpClient();
        RequestBody formBody = new FormBody.Builder()
                .add("bloodgroup",bloodgroup)
                .build();
        Request request = new Request.Builder()
                .url("http://blooddonation.byethost6.com/GetDonorsDetails.php")
                .post(formBody)
                .build();
        try {
            Response response = client.newCall(request).execute();
            String res = response.body().string();
            Log.e("responseaaa",res);
            // Do something with the response.
        } catch (IOException e) {
            e.printStackTrace();
            Log.e("responseaaa","with error "+e.toString());
        }
 
    