dynamic-200.13.8.216.fbnet.com.br has no MX records.
Question and response
Question
dig dynamic-200.13.8.216.fbnet.com.br. MX
Answer
The response has no answer records.
Authority
fbnet.com.br. 38400 SOA ns1.fbnet.com.br. junior.fbnet.com.br. 1217852253 10800 3600 604800 38400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0