I think I know why – the structure of the page changes when there are no results, and the results container element no longer exists, so the plugin can’t do a “replacement”, as it’s no longer in the response.
Usually a recommend a different DOM selector for the settings, but in this case it might be a bit more complicated, as the whole container needs to be selected. That may not be ideal, but you can try this selector:
#brx-content
You can change that here: https://i.imgur.com/jhwyOPA.png
