Hello,
As you can see, a popup window is expecting, from this many reasons can lead to this kind of issue.
Can you try to test with 
ProtoStar in order to see if that solve your issue, if yes it's linked to your 
template and so contact his creator.
If no,  so for this idea can you provide :
- 
User access to affiliate (use our 
	Contact Us
, add an 
url link to this topic).
- A screenshot of  your 
General display options (in 
Components => 
HikaShop => 
Configuration, then 
Display tab), like this :
Awaiting news from you.
Regards