Why is the price of the item 0?

Question

Netcat CMS

Hello!
(didn't work with netcat)

<!-- Цена для покупателя -->
<? if ($item['ItemPrice']): ?>
    <div class="tpl-property-item-price"><span class="tpl-value"><?= $item['ItemPriceF'] ?></span></div>
<? elseif ($item['ItemPriceRange']): ?>
    <!-- Выводит 0 если размер 1 -->
    <!-- ItemPriceRange	Строка с отформатированным диапазоном цен на товар вида «от MIN до MAX» -->
    <div class="tpl-property-item-price tpl-property-item-price-range"><?= $item['ItemPriceRange']  ?></div>
<? endif; ?>

In general, the situation is this, on the store’s website, if there are several sizes, then the price is displayed normally, but if the product has 1 size, then the price is 0.
I read this dock netcat.ru/developers/docs/modules/module-netshop/p...
Like me I understand that means an error in setting up the online store component?
Thanks