Empty shopping cart

-- HikaShop version -- : 2.6.3
-- Joomla version -- : 3.5.1
-- PHP version -- : 5.5.36
-- Browser(s) name and version -- : crome

When I delete the last item from the basket, it takes a long time, and then gives me a blank page appears where only the top menu, then I click on home and my home page appears with the pop-up that tells me where the cart is empty . it is possible to know if the problem is hikashop or configuration and what is the file that handles the carriage emptied?
1 where I am attaching photos to empty your cart, photo 2 and photo 3 home white screen with popup
Thank you

Ok Thanks

Here's what it looks that appears in the white page with the active debugging.
When I go on the delete button from the cart, the url of the "x" button is very long, for example if I have two products in the shopping cart when I delete the first string you see this:
www.giofoto.it/index.php?option=com_hika...pZD0xMDg=&Itemid=108

and it was done very fast, if I cancel the latest product is the string this:
www.giofoto.it/index.php?option=com_hika...kPTEwOA==&Itemid=108

it takes a long time and then I get this error:
Fatal error: Allowed memory size of 167772160 bytes exhausted (tried to allocate 64 bytes) in /home/uarkuuq2/domains/giofoto.it/public_html/libraries/joomla/database/driver/mysqli.php on line 886

Hello, I enabled debugging joomla and the only error message that gives me is what I reported. To set the redirect link, to get the message "empty cart" which url should I enter?