/**
  * @name update
  * @description update an item
  * @param int $id
  * @param string $name
  * @return mixed
  */
 private function update($id, $name)
 {
     $item = new Items();
     if ($item->update($id, $name)) {
         return $this->response('', 'Item has been updated', false);
     }
     return $this->response('', "Could not update the item {$id}", true);
 }
<?php

error_reporting(E_ALL);
ini_set('display_errors', 1);
// load the items class
require_once '../classes/concertClass.php';
$response = array('error' => true, 'message' => '');
if (isset($_POST['id']) && isset($_POST['name'])) {
    $id = $_POST['id'];
    $name = $_POST['name'];
    $items = new Items();
    // update the item
    if ($items->update($id, $name)) {
        $response['error'] = false;
        $response['message'] = 'Item has been updated';
    } else {
        $response['message'] = 'Could not update the item';
    }
} else {
    $response['message'] = 'Missing id value';
}
// json response
echo json_encode($response);
        $upError[] = "Type not found";
    } elseif (strlen($upTitle) < 1) {
        $upError[] = "enter title";
    } elseif (strlen($upGenre) < 1) {
        $upError[] = "enter genre";
    } elseif (strlen($upDescription) < 1) {
        $upError[] = "enter description";
    } elseif (strlen($upPrice) < 1) {
        $upError[] = "enter price";
    } elseif (strlen($upRP) < 1) {
        $upError[] = "enter rentperiod";
    } elseif (!isset($upStatus)) {
        $upError[] = "status not found";
    } else {
        $upI = new Items($upType, $upNo, $upTitle, $upGenre, $upDescription, $upPrice, $upRP, $upStatus);
        $upI->update();
    }
}
?>
  
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <!-- The above 3 meta tags *must* come first in the head; any other head content must come *after* these tags -->
    <meta name="description" content="">
    <meta name="author" content="">
    <title>Inventory</title>