For those wanting the details: I am using LetsEncrypt on AWS Lightsail.
first I stopped the services:
sudo /opt/bitnami/ctlscript.sh stop
Next I removed the certificates from the /opt/bitnami/apache2/conf folder. The were named server.crt, server.key and server.csr
And then I went to the letencrypt folder and recreated a cert:
sudo ./certbot-auto certonly --standalone -d www.fakedomain.com
Finally, I linked to the new certs in the apache/conf folder.
sudo ln -s /etc/letsencrypt/live/www.fakedomain.com/privkey.pem /opt/bitnami/apache2/conf/server.key
sudo ln -s /etc/letsencrypt/live/www.fakedomain.com/fullchain.pem /opt/bitnami/apache2/conf/server.crt
sudo chown root:root /opt/bitnami/apache2/conf/server*
sudo chmod 600 /opt/bitnami/apache2/conf/server*
the full instructions for creating the cert were found at: