Cerbot adds a suffix 000x to domains that match any previously attempt in the certbot certificates list. This causes an issue, as the script won't be able to determine it.
This can be fixed manually at the moment, after a failed setup by:
Delete the matching cases
sudo certbot delete --cert-name foobar.domain.com-0001
In advance, could maybe hint the user.
Hypotetically,
certbot certificates | grep -q 'Domains: xxx'