How do I get Flash and Nginx to Communicate with each other?

I am trying to get a Ruby with Roda website up and running using Flash with Nginx. However, each time I try to set it up I keep getting Bad Gateway or Forbidden errors to appear on the screen. I am keeping bundler and gem files away from the /var/www path since google suggests that I put them in a different folder. So, I keep it in the user folder instead.

I know I am pretty close to getting it to work, but I don’t know what I am missing. Any advice would be greatly appreciated.

Current Error:

# 403 Forbidden

---

nginx/1.24.0 (Ubuntu)

Gemfile code:

source 'https://rubygems.org'
gem 'roda'
gem 'falcon'

App code:

# app.rb
require "roda"

class App < Roda
  route do |r|
    # Root route (/)
    r.root do
      "Hello from Roda running asynchronously on Falcon!"
    end
  end
end

Config code:

# config.ru
require 'bundler/setup'
require_relative "app"

# Freezing the app structure optimizes memory and thread safety in production
run App.freeze.app

Falcon code:

#!/usr/bin/env falcon-host
require 'falcon/environment/rack'

# Bind to a local port or socket
host "duelingpets-Dev" do
  # Bind locally to port 3000 (Nginx will proxy to this)
  bind "http://127.0.0.1:3000"
  include Falcon::Environment::Rack
end

Ngnx code:

server {
    listen 80;
    server_name bat.duelingpets.net;

    # Optional: Serve static files directly via Nginx
    root /var/www/duelingpets-Dev;
    location / {
       try_files $uri $uri/ @falcon;
    }

    location @falcon {
        proxy_pass http://127.0.0.1:3000;
        proxy_set_header Host $http_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;
    }
}

Falcon Roda Service

[Unit]
Description=Falcon Server for Roda App
After=network.target

[Service]
Type=simple
User=[deploy]
WorkingDirectory=/var/www/duelingpets-Dev
ExecStart=/home/[deploy]/duelingpets-gems/.bundle exec falcon serve
Restart=always
Environment=RACK_ENV=production

[Install]
WantedBy=multi-user.target