"Internal Error" received when attempting to Request a New Certificate from Let's Encrypt via NPM while using PiHole with Unbound as self-hosted DNS

[Jokerswild2412]

Hey guys,

Sorry if this isn't the place to do this but I've run into a brick wall. First, please note that I've been following this guide pretty strictly:https://www.wundertech.net/how-to-self-host-bitwarden-on-a-raspberry-pi/

So when I attempt to request a new certificate from Let's Encrypt within Nginx Proxy Manager, I get an "Internal Error" pop-up. I've installed NPM in Docker, and forwarded ports 80 and 443 for the machine that NPM is sitting on and I have DuckDNS pointing to my router's external IP. Interestingly, when I do a port scan via whatsmyip.org it shows that port 443 is open but port 80 is not. It does appear that my ISP, Google Fiber, allows port 80 to be open, so I'm not sure if that's why I'm getting the internal error or not.

What are some next steps I could do to resolve this issue with NPM?