certbot letsencrypt – does mail server need to be included in Domains to avoid TLS library error?

Host: Digital Ocean OS: CentOS 7 Mail Server: Postfix (new install) SSL: certbot and letsencrypt. I’m trying to track down an error I’m having with postfix and I think possibly my SSL certificate. When I use the sendmail command to test postfix the mail doesn’t send and I get an error. Jan 16 19:57:15 centos-s-1vcpu-1gb-sfo2-01…