Ajax调用嵌套的php文件

I am doing a ajax POST request to a php file. Lets call it A.php

This A.php file would then call B.php.

$.ajax({
            type: "POST",
            url: "../../page_components/A.php",
            data: { // my data
            },
            success: function(response) {
                location.reload();
            },

Problem Facing: The success function is not called when A.php calls B also. It works fine if A.php doesn't call B.php

On my A.php

/* some stuff that a.php does
*/
include ('B.php'); // call B.php to handle other stuff

B.php

<?php

require '../../../../PHPMailer/class.phpmailer.php';
require '../../../../PHPMailer/class.smtp.php';

// set relevant agency email to send to. $agency comes from A.php
switch ($agency) {
    case "1": $receiverEmail = "xxx@hotmail.com";
    break;
    case "2" : $receiverEmail = "zzz@gmail.com";
    break;
}


$mail = new PHPMailer();

// All the mail setting and stuff is here...
if(!$mail->Send()) {
  echo 'Message was not sent.';
  echo 'Mailer error: ' . $mail->ErrorInfo;
} else {
  echo 'Message has been sent.';
}
?>

url: "../../page_components/A.php"

is that url supposed to be sending on B.php? if it is then isnt the url supposed to be like this

url: "../../page_components/B.php"