fibranetbrasil.net.br has no MX records.
Question and response
Question
dig fibranetbrasil.net.br. MX
Answer
The response has no answer records.
Authority
fibranetbrasil.net.br. 30 SOA ns1.infortel.net.br. noc.infortel.net.br. 2022050619 3600 800 86400 30
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0