I can't get my asp.net mvc to use ssl when being hosted on a digitalocean droplet

I can’t get my dotnet mvc app to be hosted correctly over ssl (https). It only works over http. The following is my relevant nginx files (with "example.org" used instead of my domain)

/etc/nginx/sites-enabled/default

# Default server configuration
#
server {
    server_name   example.org *.example.org;
    location / {
            proxy_pass         http://127.0.0.1:5000;
            proxy_http_version 1.1;
            proxy_set_header   Upgrade $http_upgrade;
            proxy_set_header   Connection keep-alive;
            proxy_set_header   Host $host;
            proxy_cache_bypass $http_upgrade;
            proxy_set_header   X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header   X-Forwarded-Proto $scheme;
    }

    # SSL configuration

    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/example.org/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/example.org/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot

}

server {
    listen   80 default_server;
    # listen [::]:80 default_server deferred;
    return   444;
}

server {
    if ($host = example.org) {
        return 301 https://$host$request_uri;
    } # managed by Certbot


    listen        80;
    server_name   example.org *.example.org;
    return 404; # managed by Certbot

}

/etc/nginx/nginx.conf

user www-data;
worker_processes auto;
pid /run/nginx.pid;
include /etc/nginx/modules-enabled/*.conf;

events {
        worker_connections 768;
        # multi_accept on;
}

http {

        ##
        # Basic Settings
        ##

sendfile on;
        tcp_nopush on;
        types_hash_max_size 2048;

        include /etc/nginx/mime.types;
        default_type application/octet-stream;

        ##
        # SSL Settings
        ##

        ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3; # Dropping SSLv3, ref: POODLE
        ssl_prefer_server_ciphers on;

        ##
        # Logging Settings
        ##

        access_log /var/log/nginx/access.log;
        error_log /var/log/nginx/error.log;

        ##
        # Gzip Settings
        ##

        gzip on;

 application/xml application/xml+rss text/javascript;

        ##
        # Virtual Host Configs
        ##

        include /etc/nginx/conf.d/*.conf;
        include /etc/nginx/sites-enabled/*;
}

/etc/nginx/proxy.conf

proxy_redirect          off;
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;
client_max_body_size    10m;
client_body_buffer_size 128k;
proxy_connect_timeout   90;
proxy_send_timeout      90;
proxy_read_timeout      90;
proxy_buffers           32 4k;

This makes my site work over "http://example.org" but not over "https://example.org". I don’t know why it won’t work over https? I tried altering my /etc/nginx/nginx.conf file to make it like the recommended documentation for asp.net hosting via Microsoft. Here’s my new /etc/nginx/nginx.conf file.

/etc/nginx/nginx.conf

user www-data;
worker_processes auto;
pid /run/nginx.pid;
include /etc/nginx/modules-enabled/*.conf;

events {
        worker_connections 768;
        # multi_accept on;
}

http {
    include        /etc/nginx/proxy.conf;
    limit_req_zone $binary_remote_addr zone=one:10m rate=5r/s;
    server_tokens  off;

    sendfile on;
    # Adjust keepalive_timeout to the lowest possible value that makes sense
    # for your use case.
    keepalive_timeout   29;
    client_body_timeout 10; client_header_timeout 10; send_timeout 10;

    upstream my-app{
        server 127.0.0.1:5000;
    }

    server {
        listen                    443 ssl http2;
        listen                    [::]:443 ssl http2;
        server_name               example.org *.example.org;
        ssl_certificate           /etc/letsencrypt/live/example.org/fullchain.pem;
        ssl_certificate_key       /etc/letsencrypt/live/example.org/privkey.pem;
        ssl_session_timeout       1d;
        ssl_protocols             TLSv1.2 TLSv1.3;
        ssl_prefer_server_ciphers off;
        ssl_ciphers               ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384;
        ssl_session_cache         shared:le_nginx_SSL:10m;
        ssl_session_tickets       off;
        ssl_stapling              off;

        add_header X-Frame-Options DENY;
        add_header X-Content-Type-Options nosniff;

        #Redirects all traffic
        location / {
            proxy_pass http://my-app;
            limit_req  zone=one burst=10 nodelay;
        }
    }
}        

When I change my /etc/nginx/nginx.conf file to the above, both "http://example.org" and "https://example.com" fail. So how do I get this app to work over https?