Looking for help setting up Nextcloud

🚧 Installation
1

I have an nginx webserver hosted at my subdomain.mydomain.com. This server is running on Ubuntu 20.04 and is configured for proxy services only. It handles all of the ssl. I am redirecting my nextcloud to another Ubuntu 20.04 server with apache and nextcloud installed. Everything is working for the most part, I would like to fix some of the Security and setup warnings on the overview page. I have read documentation on how to resolve it but most of the documentation assumes you are running nginx on the same server as nextcloud. So I am looking for a little guidance on how to best do this.

I am receiving the following message in Security warnings: The “Strict-Transport-Security” HTTP header is not set to at least “15552000” seconds.

Here is my nginx config:

upstream nextcloud {
    server 192.168.10.3;
    keepalive 32;
}
server {
    listen 80;
    listen [::]:80;
    server_name cloud.mydomain.com www.cloud.mydomain.com;
    return 302 https://$server_name$request_uri;

    # Prevent nginx HTTP Server Detection
    server_tokens off;

}

server {

    # SSL configuration

    listen 443 ssl http2;
    listen [::]:443 ssl http2;

    ssl_certificate         /etc/ssl/cert.pem;
    ssl_certificate_key     /etc/ssl/key.pem;

    server_name cloud.mydomain.com www.cloud.mydomain.com;

    add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;

    ssl_session_cache shared:SSL:10m;
    ssl_protocols TLSv1.2;
    ssl_ciphers 'ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256';
    ssl_prefer_server_ciphers on;

    client_max_body_size 2048M;
    underscores_in_headers on;

    location / {
    add_header Front-End-https on;    
	proxy_pass http://192.168.10.3;
    proxy_set_header        Host $host;
	proxy_set_header        X-Real-IP $remote_addr;
	proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
	#proxy_set_header        X-Forwarded-Proto $scheme;   
    proxy_max_temp_file_size 2048M;
    proxy_buffering off;
    proxy_read_timeout 300;
    }

    location /.well-known/carddav {
    return 301 $scheme://$host/remote.php/dav;
    }

    location /.well-known/webfinger {
    return 301 $scheme://$host/remote.php/dav;
    }

    location /.well-known/nodeinfo {
    return 301 $scheme://$host/remote.php/dav;
    }

    location /.well-known/caldav {
    return 301 $scheme://$host/remote.php/dav;
    }

}

I have added to my nginx config, but I still receive the error.

add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;

I am still a newbie at setting up nginx so any help is appreciated. Thank you