After update, the sale does not work anymore

-- HikaShop version -- : 3.0.0
-- Joomla version -- : 3.6.5
-- PHP version -- : 7.1
-- Browser(s) name and version -- : Firefox 51.0.1

Hello,
after update, the sale does not work anymore!
When I click on the basket, nothing happens.
No more products can be purchased.

Best regards Kurt

Hi,
I found the error, it was the certificate. (HTTPS: //)

best regards Kurt

Hi,
the problem, if I in the Joomla configuration the site set to https, the purchasing no longer works.
Shopping only works, if the https is set to off in the Joomla configuration.
What can I do!

Best regards Kurt

Hi,

What if you turn off the "add to cart legacy" setting of the HikaShop configuration in order to use the new add to cart system ?
It should better work than the legacy, old, one.