Test altertnate filter https://free.searchandfilter.com/
how-do-australian-governments-work is an invalid category slug.
Help Note: If you have changed/updated KB category slug, then please make sure you have updated new slug value in to shortcode too. <br />For example - old slug was 'old-demo' and new slug is 'new-demo'. Then shortcode will be [bkb_category categories='new-demo'] .<br />