Why is nginx returning a 405 error?

Question

Django

Good afternoon.
Deployed a Django site using gunicorn+superviror+nginx.
The site took off - everything is ok.
In the admin panel, I add news with a picture - 405 arrives. post is not allowed.
site config:

upstream app_server {

  server unix:/tmp/PMC.sock fail_timeout=0;
}

server {

    listen   80;
    server_name site.ru;

    access_log /home/venv/PMC/logs/nginx-access.log main;
    error_log /home/venv/PMC/logs/nginx-error.log debug;

    location /static/ {
        alias   /home/venv/PMC/static/;
        access_log off;
    }

    location /media/ {
        alias   /home/venv/PMC/media/;
        access_log off;
    }

    location / {
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header Host $http_host;
        proxy_redirect off;

        if (!-f $request_filename) {
            proxy_pass http://app_server;
            break;
        }
    }
}

I understand that nginx does not allow Post to static.