mx1.ajato.com.br has no CNAME records.
Question and response
Question
dig mx1.ajato.com.br. NS
Answer
The response has no answer records.
Authority
ajato.com.br. 1279 SOA aquarius.vivo.com.br. root.ajato.com.br. 2106077921 10200 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0