Can't access Costco.co.uk website on laptop.

Hi all,  I have NIS and have been trying to access Costco.co.uk but with no success.   It asks me to accept the cookies but everytime I click on the accept button it just comes back up again.  I have searches the internet for an answer for around an hour without success.   This should be so easy but I don't find NIS very initiative although that may just be me.   I've gone into the setting area, network, smart firewall but don't know what to do next and can't find any help guides on this.   

 

I have to say that Costco.co.uk is the only website that I have this problem with and I don't know why that is.  Any help would be appreciated.

 

Thanks