smtp.wind.net.do has no CNAME records.
Question and response
Question
dig smtp.wind.net.do. NS
Answer
The response has no answer records.
Authority
wind.net.do. 3060 SOA ns2.wind.com.do. hostmaster.wind.com.do. 2011113029 900 600 86400 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0