Hi,
Thanks, I finally got it.
It is something I already fix for HikaMarket 1.6.0 so that's why I couldn't reproduce it in my local websites.
You have to edit the file "administrator/components/com_hikamarket/helpers/helper.php" and replace the line
$query = 'SELECT count(a.product_id) FROM ' . hikamarket::table('shop.product') . ' AS a WHERE a.product_id = '. (int)$product_id . ' AND a.product_vendor_id = ' . (int)$vendor_id;
By
$query = 'SELECT count(pr.product_id) '.
' FROM ' . hikamarket::table('shop.product') . ' AS pr '.
' LEFT JOIN ' . hikamarket::table('shop.product') . ' AS pa ON (pr.product_type = ' . $db->Quote('variant') . ' AND pa.product_id = pr.product_parent_id) '.
' WHERE pr.product_id = '. (int)$product_id . ' AND (pr.product_vendor_id = ' . (int)$vendor_id . ' OR (pr.product_vendor_id = 0 AND pa.product_vendor_id = ' . (int)$vendor_id . '))';
and it will fix the issue.
Regards,