When Google finds duplicate pages, it can hurt your search ranking.

Unfortuneatly, Google sees www and non-www pages as two different pages. So its good to put in a redirect so only one adress gets indexed.

In the .htaccess add the following lines

## ORGANIC WEBS - rewrite www to non-www to fix canonical issues
##
RewriteEngine On
RewriteCond %{HTTP_HOST} ^www.mywebsite.com.au [NC]
RewriteRule ^(.*)$ https://mywebsite.com.au/$1 [L,R=301]