Ajax：功能不起作用

I don't know why my code does not work onclick, but there is no pop up. The AJAX function var phone and id got data, but the AJAX did not. Is there anything wrong with the script? Does the AJAX need a jQuery library?

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/core.js"></script>
<script type="text/javascript">
  function clickButton() {
    var phone = document.getElementById('phone').value;
    var id = document.getElementById('id').value;
    $.ajax({
      type: "post",
      url: "userDetaiAjax.php",
      data: {
        'phone': phone,
        'id': id
      },
      cache: false,
      success: function(html) {
        alert('Data Send');
        $('#msg').html(html);
      }
    });
    return false;
  }
</script>
<div class="col">
  <div class="form-group">
      <h6>
        <label>Name :</label>
        <?php echo $name ?>
      </h6>
      <h6>
        <label>Email :</label>
        <?php echo $email ?>
      </h6>
      <input type="" name="phone" id="phone">
      <input type="" name="id" id="id" value="<?php echo $_SESSION[" staff_id "];?>" hidden>
      <h6>
        <label>Phone :</label>
        <?php echo $phone ?>
      </h6>
      <input type="submit" name="aa" value="submit2" onclick="return clickButton();">
    </form>
    <p id="msg"></p>
  </div>
</div>
</div>
</div>

for the url

<?php 
$phone = $_POST['phone'];
$id = $_POST['id'];
echo 'success';
echo $phone;
echo $id;

$a='"USR_ID"';
$b='"phone"';
include 'conn.php';
if (!$conn) {
    $e = oci_error();
    trigger_error(htmlentities($e['message'], ENT_QUOTES), E_USER_ERROR);

}

   $query = "update usr_web SET phone=:c1 WHERE usr_id=:c2";

              $stid = oci_parse($conn, $query);

   oci_bind_by_name($stid, ":c1", $phone);
   oci_bind_by_name($stid, ":c2", $id);


                                 $result = oci_execute($stid);
                                 oci_free_statement($stid);
                                 oci_commit($conn);
                                  oci_close($conn);
                            echo $result;

?>

U have error in your console:

$ is not defined

Which mean u did not include jquery, so u should add this code after ajax include:

<script
  src="https://code.jquery.com/jquery-3.3.1.min.js"
  integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8="
  crossorigin="anonymous"></script>

U can chack your console errors with F12 key in browser and tab Console.

When you open the console of your browser you should see an error message like "ReferenceError: $ is not defined". So it seems that $ is not part of core.js which you have loaded. Just load the full version (https://code.jquery.com/jquery-3.3.1.min.js) and it should work.