Bitrix API why the product is not added to the cart?

Question

1C-Bitrix

I send the quantity and ID of the goods through Ajax. Why is it not added to the cart? tell me plz. post comes.
$_POST['id'] - product id

<?require($_SERVER["DOCUMENT_ROOT"] . "/bitrix/modules/main/include/prolog_before.php");

  //$count = $_POST['count'];
  //$id = $_POST['id'];
  	$add = $_POST['add'];
  $mess = '';
  $PRICE_ID = '1';

//CModule::IncludeModule('iblock');
  CModule::IncludeModule('catalog');
//CModule::IncludeModule('currency');
  CModule::IncludeModule("sale");

?>

<?
if (CModule::IncludeModule("catalog") && CModule::IncludeModule("sale")) {

  // ADD TO CART
  if ($_POST['id']) {

    $count = ($_POST['count']) ? $_POST['count'] : 1;

    $result = Add2BasketByProductID(
      $_POST['id'],
      $count
    );
  }


  // UPDATE QUANTITY
  if ($_POST['update'] == 'Y' && $_POST['id'] && $_POST['count']) {
    $arFields = array(
      "QUANTITY" => $_POST['count'],
    );
    CSaleBasket::Update($_POST['id'], $arFields);
  }

  // DELETE PRODUCT
  if ($_POST['delete'] == 'Y' && $_POST['id']) {
    CSaleBasket::Delete($_POST['id']);
  }

}
else { echo "Не подключены модули"; }
AddMessage2Log("<br/><br/><pre>".print_r($result,true)."</pre><br/><br/>", "test");
echo $mess;
require($_SERVER["DOCUMENT_ROOT"]."/bitrix/modules/main/include/epilog_after.php");
?>

Answer 1

Didn't understand your writing. Add a product like this:

Bitrix\Main\Loader::includeModule("catalog");
$fields = [
    'PRODUCT_ID' => 98
    'QUANTITY' => 2
];
$r = Bitrix\Catalog\Product\Basket::addProduct($fields);
if (!$r->isSuccess()) {
    var_dump($r->getErrorMessages());
}