I did not find any issue on the Apache error logs...
I noticed you are using Varnish so it redirects the request to Apache. Could you please check that Varnish is running? Please run the command below and share the output:
sudo /opt/bitnami/ctlscript.sh status
If Varnish is not running, please run the command:
sudo /opt/bitnami/ctlscript.sh start varnish