dns2.alterna.com.br has no MX records.
Question and response
Question
dig dns2.alterna.com.br. MX
Answer
The response has no answer records.
Authority
alterna.com.br. 3600 SOA ns.alterna.com.br. root\@ns.alterna.com.br. 2025101301 3600 600 1209600 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0