You need to increase the size limit in nginx.conf or in your domain.com.conf. Add ‘client_max_body_size xxM’ inside the server section, where xx is the size (in megabytes) that you want to allow.

http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;

    server {
        client_max_body_size 20M;
        listen       80;
        server_name  localhost;

        # Main location
        location / {
            proxy_pass         http://127.0.0.1:8000/;
        }
    }
}