smtp.falconcorp.com.br has no MX records.
Question and response
Question
dig smtp.falconcorp.com.br. MX
Answer
The response has no answer records.
Authority
falconcorp.com.br. 300 SOA ns1-02.azure-dns.com. domains.ontexglobal.com. 65 3600 300 2419200 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0