PHP wont return anything to AJAX when adding certain Function

Niko :

I am confused my PHP wont return anything to AJAX when I added my decrypt Function

MY PHP Files:

$key = "Secret Key";
function decryptthis($data, $key)
{
    $encryption_key = base64_decode($key);
    list($encrypted_data, $iv) = array_pad(explode('::', base64_decode($data), 2), 2, null);
    decryptthis($encrypted_data, 'aes-256-cbc', $encryption_key, 0, $iv);
}

session_start();
$user = $_SESSION['username'];
$bulan = $_POST['bulan'];
$tahun = $_POST['tahun'];
$res = array();

$result = mysqli_query($con, "select * from tb_payslip where NIP ='$user' AND bulan='$bulan' AND tahun='$tahun'");
$rowCheck = mysqli_num_rows($result);
if ($rowCheck > 0) {
    while ($row = mysqli_fetch_array($result)) {

        $res['cabang'] = $row['cabang'];
        $res['NIP'] = $row['NIP'];
        $res['u_gaji_pokok'] = decryptthis("$row[u_gaji_pokok]", $key);//When i added this function wont return anything
        $res['bulan'] = $row['bulan'];
        $res['tahun'] = $row['tahun'];
        $res['response'] = "ok";
    }
}

echo json_encode($res);

MY AJAX that would return the result:

$("#generate-payslip").click(function (e) {
    e.preventDefault();
    $.ajax({
        type: 'POST',
        url: 'generate-payslip.php',
        data: $('.form-pdf').serialize(),
        dataType: 'json',
        success: function (resp) {
            if (resp.response == "ok") {

                $('#payslip-title').html("SLIP GAJI " + returnbulan(resp.bulan) + " " + resp.tahun);
                $("#cabang").html(resp.cabang);
                $('#u_gaji_pokok').html(resp.u_gaji_pokok);
            }
        })

When I run the code, my AJAX would return nothing, but when I delete the Decryptthis Function, the AJAX will Return all the result as intended.

Please Help I am really confused as to why in wont work

arma :

You have infinite loop right there. decryptthis() is calling itself

remove the inner one and you should be fine.