Site Categories Plugin - Issue with "Next Page" display function

Hello,

We have been using the Site Category plugin to display categories of sites on our multisite. However, we have been experiencing an issue where the, "Next Page," button loops to the current page rather than displaying the next set of sites. For an example, see the screenshot and this link: https://ds.lclark.edu/site-categories/?category=student-sites&start_at=2.

Any help in diagnosis and solving this issue would be much appreciated. Please, let me know if there's anything I can do to help on my end.

Thanks so much,
Nate Stoll