Start gunicorn with Nginx forwarded headers allowed.

gunicorn.md

Start gunicorn

gunicorn -w 3 --forwarded-allow-ips="10.170.3.217,10.170.3.220" app:server

Nginx server block

server {
    listen 80;
    server_name "";
    location / {
        proxy_pass http://127.0.0.1:8000;
        proxy_set_header Host $host:
        proxy_set_header X-Forwarded_for $proxy_add_x_forwarded_for;
    }
}