Poorly optimized

I installed packlink plugin in my woocommerce site and suddenly, orders page went really slowly. 
Recently (maybe with an update) loading pages, saving pages and add to cart button also go terrible slowly.

I installed queryMonitor and saw more than 500 querys like this:
SELECT *
FROM wp_packlink_entity
WHERE type = 'ShippingService'
LIMIT 0, 1

every time i load a page, update a page, product, add to cart, load orders list etc..

i 'temporary patched' this situation creating and index in type column, but i think this is not the correct solution.

Please, fix this problem