1. Conduct following code

    cd /opt/bitnami/letsencrypt

    sudo ./certbot-auto certonly --webroot -d DOMAIN -d www.DOMAIN

    Input webroot: /opt/bitnami/apps/wordpress/htdocs

    Cruise site webroot: /opt/bitnami/apache2/htdocs
  2. Restart bitnami

    sudo /opt/bitnami/ctlscript.sh restart apache