I'm trying to create a Let's Encrypt certificate, and it seems pretty straight forward, but I can't get it to work.
First off, I've got a domain from no-ip, *.dynns.com (payed). Do they work? If not, what should I be getting?
The message I'm getting (roughly translated from Norwegian): " *.dynns.com er invalid. Make sure the domain name can be connected to through port 80 (Ref. 5041)."
I tried to forward port 80 to my Asustor, but that didn't help. Is there any other settings I'm missing? Sorry if missing something very obvious here....

Any help is much appreciated!

-bobby light