PHP JSON Response

<?php
    session_start();

    include "../webconfig.php";

    $identitas = mysqli_real_escape_string($connect, $_POST['identitas']);
    $password = mysqli_real_escape_string($connect, $_POST['password']);

    $password1 = 'pemilu2017';

    $query = mysqli_query($connect, "SELECT * FROM data_pemilih WHERE identitas = '$identitas'");

    $cek = mysqli_num_rows($query);

    if ($cek == 1 && $password == $password1) {
        $ambil = mysqli_fetch_assoc($query);
        $nama = $ambil['nama'];
        $kelas = $ambil['kelas'];
        $status = $ambil['status'];

        if ($status == 'Nonaktif') {
            $response['validasi'] = "Nonaktif";
            echo json_encode($response);
        }elseif ($status == 'Selesai') {
            $response['validasi'] = "Selesai";
            echo json_encode($response);
        }else {
            $_SESSION['identitas'] = $identitas;
            $_SESSION['nama'] = $nama;
            $_SESSION['kelas'] = $kelas;
            $_SESSION['status'] = $status;

            $response['identitas'] = $identitas;
            $response['kelas'] = $kelas;
            $response['status'] = $status;
            $response['validasi'] = "Register";

            echo json_encode($response);
        }

    } else {
        $response['validasi'] = "Salah";
        echo json_encode($response);
    }
?>