How to renew a LetsEncrypt SSL cert without using port 80?

Configuration
1

I’ve created an SSL certificate using LetsEncrypt. I needed to temporarily redirect port 80 on my router to my HA server to do it. I now need to renew the certificate, but if I try to use the following command:

 certbot renew --quiet --no-self-upgrade --standalone --preferred-challenges tls-sni-01 --tls-sni-01-port 8123 --pre-hook "sudo docker stop home-assistant" --post-hook "sudo systemctl start home-assistant"

…I get this error:

Client with the currently selected authenticator does not support any combination of challenges that will satisfy the CA. Attempting to renew cert (mydomain.ddns.net) from /etc/letsencrypt/renewal/mydomain.ddns.net.conf produced an unexpected error: Client with the currently selected authenticator does not support any combination of challenges that will satisfy the CA.. Skipping. All renewal attempts failed. The following certs could not be renewed:  /etc/letsencrypt/live/mydomain.ddns.net/fullchain.pem (failure)

Is there any way of renewing my SSL cert without having to redirect port 80 to my HA server?
I’m running HA core v2021.7.4 in a Docker container on a Lubuntu VM. I have installed the Certificate Expiry integration but it has always shown this error in the HA console:

! Retrying setup: Connection timeout with server: mydomain.ddns.net:443

I have port 443 forwarded to my HA server, but that doesn’t seem to help.

2

I simply open port 80, renew cert and then close port 80, as its every 3 months it’s no big deal.

Don’t believe you can do it without port 80 open.

3

Do you know if redirecting port 80 from my main web host (specifically for requests to my HA domain) would work? My main web host is an IIS7 server on the same LAN.
I don’t know how I would do this, but that’s something that I could investigate if the idea is feasible.

4

Sorry I have no idea, it’s all relatively new to me to be honest, I just know that it uses port 80 to renew and that’s all it needs it for, hence why I close port 80 permanently other than when renewing cert.