error con los pedido en virtuermart

vmError: exeSortSearchListQuery Unknown column ‘u.first_name’ in ‘field list’ SQL=SELECT SQL_CALC_FOUND_ROWS o.*, CONCAT_WS(‘ ‘,u.first_name,u.middle_name,u.last_name) AS order_name ,pm.payment_name AS payment_method FROM vk76f_virtuemart_orders as o LEFT JOIN vk76f_virtuemart_order_userinfos as u ON u.virtuemart_order_id = o.virtuemart_order_id AND u.address_type=”BT” LEFT JOIN

tengo ese gran error que no me permite ver los pedido que hacen los compradores 🙁 ayuda