mail.winnethost.com has no CNAME records.
Question and response
Question
dig mail.winnethost.com. NS
Answer
The response has no answer records.
Authority
winnethost.com. 10723 SOA dns4.winnethost.com. hostmaster.winnethost.com. 2015061726 1800 900 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0