dns4.ctitech.net.br has no MX records.
Question and response
Question
dig dns4.ctitech.net.br. MX
Answer
The response has no answer records.
Authority
ctitech.net.br. 900 SOA dns1.ctitech.net.br. postmaster.ctitech.net.br. 2025121801 28800 1800 604800 900
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0