@justoverclock Ok, that’s because you have no wildcard DNS record, and it’s attempting to renew for domains you don’t have listed in DNS.
Select the second option, and enter justoverclock.it
and proceed that way.
Note, that there is a rate-limit set to 10 per hour, so if you exceed this, you’ll need to wait for a while then try again. In this case, you’d see this message
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator webroot, Installer None
Renewing an existing certificate
An unexpected error occurred:
There were too many requests of a given type :: Error creating new order :: too many failed authorizations recently: see https://letsencrypt.org/docs/rate-limits/
Please see the logfiles in /var/log/letsencrypt for more details.