“Date” is displayed when there are no search criteria, and “Relevance” is displayed otherwise. It seems that there’s a redirect to the search page when the sorting option is changed, will try to fix this in the next version.
Thanks, will check this before releasing the next version. If you’re familiar with CSS you can check this extra space via the web inspector and temporarily fix it. As a temporary for Date/Relevance please simply rename “Relevance” to “Date” using Loco Translate (or another translation plugin of your choice), then there will be the same sorting option.