mx.telium.com.br has no CNAME records.
Question and response
Question
dig mx.telium.com.br. NS
Answer
The response has no answer records.
Authority
telium.com.br. 92 SOA telium.com.br. postmaster.telium.com.br. 2026021204 10800 3600 604800 14400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0