Portfolio items not sorting into groups in wordpress

I am working in Wordpress 4.4 running Child CoWorker Theme, and I am having issues with my portfolio. I have created 47 portfolio items, and each item is assigned a group. There are a total of 8 groups. In the portfolio page when you click on a portfolio item, the page refreshes, but nothing is sorted. Also, when I look at the plugins page, I don't see a portfolio plugin. I did not install it, so I am not sure which portfolio it is, but it looks great in the site, it just doesn't sort at all.

Here is more information. When I click on a specific portfolio item, it has its category listed, and when I click on the category name I go to a page with all the correct portfolio items listed in that group. But, when I try to sort from the main portfolio page and click on a category, it does not sort. On the main page, this is what the code looks like for the category links: Art Tour

This # above needs to be replaced with a url, right? In the portfolio, it says that each category has a 'slug' and it just has the name 'art-tour' for this slug, but I think it needs the right URL for the page with all the art tours on it. Thanks!

via Chebli Mohamed