Hi there,

It sounds like that the Django service is not running. I could suggest following the steps here on how to troubleshoot common problems with Django:

https://www.digitalocean.com/community/tutorials/how-to-set-up-django-with-postgres-nginx-and-gunicorn-on-ubuntu-16-04

Mainly try out the following commands:

• First check the Nginx error log for the exact error why it is returning 502:

tail -100 /var/log/nginx/error.log

• Check the system logs for the Gunicorn service:

sudo journalctl -u gunicorn

Usually, 502 is returned by Nginx when it fails to connect to the backend service, which indicates that it is either a problem with the Nginx configuration or the backend service is unavailable.

Here is a quick video on how to troubleshoot a 502 error, though it uses Docker as an example:

Regards,
Bobby