Want to expose HA securely for the app via DuckDNS + NPM on a fritzos router

Hi guys, I am trying to get a DuckDNS + NPM setup to run on my fritzOS router but having significant trouble because I have very little idea about network administration and need some help.

What I have:

  • a running duckDNS domain that I can ping and gets successfully resolved to my public IP.
  • a proxy host in NPM with a subdomain on the duckdns domain that I want to route to my homeassistant that is marked active.
  • an SSL certificate in NPM for the duckdns domain via Letsencrypt that is also marked active and assigned to the proxy host.
  • DNS rebind exceptions in FritzOS for the duckdns domain + HA subdomain
  • Port exceptions for my HA server on port 443 and port 80 as recommended by NPM doc.
  • Got a second DuckDNS domain because that seems to work for some people but not for me.
  • Logs of NPM, DuckDNS, MariaDB look fine.

But I always get timeouts when I try to reach the duckdns HA subdomain regardless of whether I am trying to connect internally or externally.

This is my configuration.yaml:

http:
  use_x_forwarded_for: true
  trusted_proxies:
    - 172.30.33.0/24
    - 172.16.0.0/12
    - 127.0.0.1
    - 192.168.178.43
    - ::1
  cors_allowed_origins:
    - https://google.com
    - https://www.home-assistant.io
    - https://cast.home-assistant.io

Where did I make an error?