Why are some products displayed with a zero price in the viewed products component in Bitrix?

Question

CMS

Good afternoon!
There is a site on the editorial office Small Business. The catalog has a block of viewed products, which is displayed using the bitrix:sale.viewed.products component. So I noticed one oddity: for some goods, the price in this block is zero, although the price is set. I displayed the $arResult array, it turned out that the price was already initially transferred equal to 0. I thought that the reason was the difference in the values ​​​​of any fields, but comparing the product with the displayed and non-displayed price, I did not find any differences.
What could be the reason?