Questions about Category Drop Down

Hello,

On this page (https://wiksmart.marketequine.com/) there is a drop down named 'Category', when you select the drop down, then select 'Blankets' it goes to this page (https://wiksmart.marketequine.com/category/blankets/) with a 404 Error.

Can someone help me this this?

I have already granted access to my site for you to help!

Thanks!
E,