Does Bitrix add the same product separately?

Question

1C-Bitrix

I'm making up a template for Bitrix, the first experience. And I ran into a problem that I did not understand...
in general, there is a component on the main page bitrix:catalog.top with standard settings,

<?$APPLICATION->IncludeComponent(
  "bitrix:catalog.top", 
  ".default", 
  array(
    "IBLOCK_TYPE_ID" => "catalog",
    "IBLOCK_ID" => "5",
    "ELEMENT_SORT_FIELD" => "name",
    "ELEMENT_SORT_ORDER" => "asc",
    "ELEMENT_SORT_FIELD2" => "name",
    "ELEMENT_SORT_ORDER2" => "asc",
    "HIDE_NOT_AVAILABLE" => "N",
    "ELEMENT_COUNT" => "6",
    "LINE_ELEMENT_COUNT" => "3",
    "PROPERTY_CODE" => array(
      0 => "MINIMUM_PRICE",
      1 => "MAXIMUM_PRICE",
      2 => "",
    ),
    "OFFERS_FIELD_CODE" => array(
      0 => "NAME",
      1 => "",
    ),
    "OFFERS_PROPERTY_CODE" => array(
      0 => "ARTNUMBER",
      1 => "COLOR_REF",
      2 => "SIZES_SHOES",
      3 => "SIZES_CLOTHES",
      4 => "MORE_PHOTO",
      5 => "",
    ),
    "OFFERS_SORT_FIELD" => "sort",
    "OFFERS_SORT_ORDER" => "asc",
    "OFFERS_SORT_FIELD2" => "id",
    "OFFERS_SORT_ORDER2" => "desc",
    "OFFERS_LIMIT" => "0",
    "VIEW_MODE" => "SLIDER",
    "TEMPLATE_THEME" => "site",
    "PRODUCT_DISPLAY_MODE" => "Y",
    "ADD_PICT_PROP" => "-",
    "LABEL_PROP" => "-",
    "OFFER_ADD_PICT_PROP" => "MORE_PHOTO",
    "OFFER_TREE_PROPS" => array(
      0 => "COLOR_REF",
      1 => "SIZES_SHOES",
      2 => "SIZES_CLOTHES",
    ),
    "SHOW_DISCOUNT_PERCENT" => "Y",
    "SHOW_OLD_PRICE" => "Y",
    "ROTATE_TIMER" => "30",
    "MESS_BTN_BUY" => "Купить",
    "MESS_BTN_ADD_TO_BASKET" => "В корзину",
    "MESS_BTN_DETAIL" => "Подробнее",
    "MESS_NOT_AVAILABLE" => "Нет в наличии",
    "SECTION_URL" => "",
    "DETAIL_URL" => "",
    "BASKET_URL" => "/site_ik/personal/cart/",
    "ACTION_VARIABLE" => "action",
    "PRODUCT_ID_VARIABLE" => "id_slider",
    "PRODUCT_QUANTITY_VARIABLE" => "quantity",
    "PRODUCT_PROPS_VARIABLE" => "prop",
    "SECTION_ID_VARIABLE" => "SECTION_ID",
    "CACHE_TYPE" => "A",
    "CACHE_TIME" => "180",
    "CACHE_GROUPS" => "Y",
    "DISPLAY_COMPARE" => "Y",
    "PRICE_CODE" => array(
      0 => "BASE",
    ),
    "USE_PRICE_COUNT" => "N",
    "SHOW_PRICE_COUNT" => "1",
    "PRICE_VAT_INCLUDE" => "Y",
    "PRODUCT_PROPERTIES" => array(
    ),
    "USE_PRODUCT_QUANTITY" => "N",
    "CONVERT_CURRENCY" => "N",
    "OFFERS_CART_PROPERTIES" => array(
      0 => "ARTNUMBER",
      1 => "COLOR_REF",
      2 => "SIZES_SHOES",
      3 => "SIZES_CLOTHES",
    ),
    "IBLOCK_TYPE" => "catalog",
    "FILTER_NAME" => "",
    "SHOW_CLOSE_POPUP" => "Y",
    "SHOW_PAGINATION" => "Y",
    "MESS_BTN_COMPARE" => "Сравнить",
    "CACHE_FILTER" => "N",
    "ADD_PROPERTIES_TO_BASKET" => "Y",
    "PARTIAL_PRODUCT_PROPERTIES" => "N",
    "ADD_TO_BASKET_ACTION" => "ADD",
    "COMPARE_PATH" => ""
  ),
  false
);?>

When I add a product, it is added to the cart, and when I go to the detailed page of the same product and click add to cart again, it is added, but for some reason it is added as a separate item, i.e. the same product is obtained twice, but the quantity must increase.
I picked and picked and took the standard template of the Bitrix online store and found out that if there is another component bitrix.catalog.top on the page (the standard one from the online store with demo data), with these settings

<?
$APPLICATION->IncludeComponent("bitrix:catalog.top", "slider", array(
  "IBLOCK_TYPE_ID" => "catalog",
    "IBLOCK_ID" => "5",
    "ELEMENT_SORT_FIELD" => "name",
    "ELEMENT_SORT_ORDER" => "asc",
    "ELEMENT_COUNT" => "6",
    "VIEW_MODE" => "SLIDER",
    "TEMPLATE_THEME" => "site",
    "PROPERTY_CODE" => array(
      0 => "MINIMUM_PRICE",
      1 => "MAXIMUM_PRICE",
      2 => "",
    ),
    "SECTION_URL" => "",
    "DETAIL_URL" => "",
    "ACTION_VARIABLE" => "action",
    "PRODUCT_ID_VARIABLE" => "id_slider",
    "PRODUCT_QUANTITY_VARIABLE" => "quantity",
    "PRODUCT_PROPS_VARIABLE" => "prop",
    "SECTION_ID_VARIABLE" => "SECTION_ID",
    "CACHE_TYPE" => "A",
    "CACHE_TIME" => "180",
    "CACHE_GROUPS" => "Y",
    "DISPLAY_COMPARE" => "Y",
    "PRICE_CODE" => array(
      0 => "BASE",
    ),
    "OFFERS_FIELD_CODE" => array(
      0 => "NAME",
      1 => "",
    ),
    "OFFERS_PROPERTY_CODE" => array(
      0 => "",
      1 => "COLOR",
      2 => "WIDTH",
      3 => "",
    ),
    "OFFERS_CART_PROPERTIES" => "",
    "USE_PRICE_COUNT" => "N",
    "SHOW_PRICE_COUNT" => "1",
    "PRICE_VAT_INCLUDE" => "Y",
    "USE_PRODUCT_QUANTITY" => "Y",
    "IBLOCK_TYPE" => "catalog",
    "ELEMENT_SORT_FIELD2" => "id",
    "ELEMENT_SORT_ORDER2" => "desc",
    "FILTER_NAME" => "",
    "HIDE_NOT_AVAILABLE" => "N",
    "LINE_ELEMENT_COUNT" => "3",
    "OFFERS_SORT_FIELD" => "sort",
    "OFFERS_SORT_ORDER" => "asc",
    "OFFERS_SORT_FIELD2" => "id",
    "OFFERS_SORT_ORDER2" => "desc",
    "OFFERS_LIMIT" => "5",
    "PRODUCT_DISPLAY_MODE" => "Y",
    "ADD_PICT_PROP" => "-",
    "LABEL_PROP" => "-",
    "SHOW_DISCOUNT_PERCENT" => "Y",
    "SHOW_OLD_PRICE" => "Y",
    "SHOW_CLOSE_POPUP" => "Y",
    "ROTATE_TIMER" => "30",
    "SHOW_PAGINATION" => "Y",
    "MESS_BTN_BUY" => "Купить",
    "MESS_BTN_ADD_TO_BASKET" => "В корзину",
    "MESS_BTN_COMPARE" => "Сравнить",
    "MESS_BTN_DETAIL" => "Подробнее",
    "MESS_NOT_AVAILABLE" => "Нет в наличии",
    "CACHE_FILTER" => "N",
    "CONVERT_CURRENCY" => "N",
    "BASKET_URL" => "/site_ik/personal/cart/",
    "ADD_PROPERTIES_TO_BASKET" => "Y",
    "PARTIAL_PRODUCT_PROPERTIES" => "N",
    "ADD_TO_BASKET_ACTION" => "ADD",
    "COMPARE_PATH" => "",
    "OFFER_ADD_PICT_PROP" => "-",
    "OFFER_TREE_PROPS" => array(
      0 => "-",
    ),
    "PRODUCT_PROPERTIES" => ""
  ),
  false,
  array(
  "ACTIVE_COMPONENT" => "Y"
  )
);
?>

Then everything works fine ... What setting I missed ... what I'm doing wrong ... I can't understand anything ...
Here is the header itself

<?if(!defined("B_PROLOG_INCLUDED") || B_PROLOG_INCLUDED!==true)die();
IncludeTemplateLangFile($_SERVER["DOCUMENT_ROOT"]."/bitrix/templates/".SITE_TEMPLATE_ID."/header.php");
//$wizTemplateId = COption::GetOptionString("main", "wizard_template_id", "eshop_adapt_horizontal", SITE_ID);
//CUtil::InitJSCore();
//CJSCore::Init(array("fx"));
//$curPage = $APPLICATION->GetCurPage(true);
?>
<!DOCTYPE html>
<!--[if IE 7 ]><html class="ie ie7 lte9 lte8 lte7" lang="ru-RU"><![endif]-->
<!--[if IE 8]><html class="ie ie8 lte9 lte8" lang="ru-RU">	<![endif]-->
<!--[if IE 9]><html class="ie ie9 lte9" lang="ru-RU"><![endif]-->
<!--[if (gt IE 9)|!(IE)]><!-->
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="<?=LANGUAGE_ID?>" lang="<?=LANGUAGE_ID?>">
<head>
  <meta http-equiv="X-UA-Compatible" content="IE=edge" />
  <meta content="width=device-width, initial-scale=1, maximum-scale=1" name="viewport">
  <!из старого шаблона<meta name="viewport" content="user-scalable=no, initial-scale=1.0, maximum-scale=1.0, width=device-width">
  <!из старого шаблона<link rel="shortcut icon" type="image/x-icon" href="<?=SITE_DIR?>/favicon.ico" />
  <?//$APPLICATION->ShowHead();
  echo '<meta http-equiv="Content-Type" content="text/html; charset='.LANG_CHARSET.'"'.(true ? ' /':'').'>'."\n";
  $APPLICATION->ShowMeta("robots", false, true);
  $APPLICATION->ShowMeta("keywords", false, true);
  $APPLICATION->ShowMeta("description", false, true);
  $APPLICATION->ShowCSS(true, true);
  ?>
  <!из старого шаблона<link rel="stylesheet" type="text/css" href="<?//=CUtil::GetAdditionalFileURL(SITE_TEMPLATE_PATH."/colors.css")?>" />
  <?
  $APPLICATION->ShowHeadStrings();
  $APPLICATION->ShowHeadScripts();
  //$APPLICATION->AddHeadScript(SITE_TEMPLATE_PATH."/script.js");
  
  
  /*Reset CSS*/
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/css/normalize.css'); 
  /*Bootstrap core CSS*/
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/css/bootstrap.css'); 
  /*Iview Slider*/
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/css/iview.css'); 
  /*Responsive 3D Menu*/
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/css/menu3d.css'); 
  /*Animations*/
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/css/animate.css'); 
  /*Custom styles for this template*/
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/css/custom.css'); 
  /*Style Switcher*/
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/css/style-switch.css'); 
  /*Color*/
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/css/skin/color.css'); 
  /*Importing Fonts and Icons*/
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/fonts/fontawesome/font-awesome.css'); 
  $APPLICATION->SetAdditionalCSS(SITE_TEMPLATE_PATH.'/fonts/lato/stylesheet.css'); 
  
  
  /*Bootstrap core JavaScript*/
  $APPLICATION->AddHeadScript(SITE_TEMPLATE_PATH."/js/jquery-1.10.2.min.js"); 
  $APPLICATION->AddHeadScript(SITE_TEMPLATE_PATH."/js/bootstrap.min.js"); 
  $APPLICATION->AddHeadScript(SITE_TEMPLATE_PATH."/js/bootstrap-select.js"); 
  /*Custom Scripts*/
  $APPLICATION->AddHeadScript(SITE_TEMPLATE_PATH."/js/scripts.js"); 
  /*MegaMenu*/
  $APPLICATION->AddHeadScript(SITE_TEMPLATE_PATH."/js/menu3d.js"); 
  /*iView Slider*/
  $APPLICATION->AddHeadScript(SITE_TEMPLATE_PATH."/js/raphael-min.js"); 
  $APPLICATION->AddHeadScript(SITE_TEMPLATE_PATH."/js/jquery.easing.js"); 
  $APPLICATION->AddHeadScript(SITE_TEMPLATE_PATH."/js/iview.js");

  ?>
  <title><?$APPLICATION->ShowTitle()?></title>
</head>
<body>
<div id="panel"><?$APPLICATION->ShowPanel();?></div>

footer

<?if(!defined("B_PROLOG_INCLUDED") || B_PROLOG_INCLUDED!==true)die();
  IncludeTemplateLangFile($_SERVER["DOCUMENT_ROOT"]."/bitrix/templates/".SITE_TEMPLATE_ID."/header.php");

?>
</body>
</html>

empty just for experimentation

Answer 1

You use trade offers from the catalog.top component, you put one trade offer in the basket, another one from the product card.