Erpnext letsencrypt gives 503 after setup using guide

I’m following this guide to setup ssl with letsencrypt:
but I’m failing miserably, nginx gives 500x response after this configuration after trying to set the ssl for my new bench called test-bench.

I did like the guide suggested:

sudo service nginx stop
certbot certonly --standalone

set the ssl_certificate and ssl_certificate_key parameters in site_config.json
bench setup nginx
sudo service nginx restart

Server gives 50x error code after this.