Since LetsEncrypt doesnt support renewal of port 443 you can use the DNS-Challenge if you are not allowed or able to use Port 80. The renew function is not working, however if you own the DNS zone and can edit it is pretty easy to create a new certificate and use a DNS-Challenge to verify you are the owner of the domain.
How to renew / get a certificate
To get a new certificate you can run the following commands:
1. Run the command below to get certbot to fetch a certificate
sudo certbot -d domain.com –manual –preferred-challenges dns certonly
2. After running you will be prompted if certbot can use your IP
3. Next it will display a TXT value you have to create. So create a new record “_acme-challenge.domain.com” and provide the string as value within ” ” (in DirectAdmin).
4. Make sure with mxtoolbox.com (txt:_acme-challenge.domain.com) to verify if the record is properly working.
5. Hit “Enter” to continue.
6. Finished! The system will output where the cert and key are saved, commonly in the /etc/letsencrypt/live/<domain>