ns4.armazemdc.com.br has no MX records.
Question and response
Question
dig ns4.armazemdc.com.br. MX
Answer
The response has no answer records.
Authority
armazemdc.com.br. 10800 SOA ns1.armazemdc.com.br. suporte.armazemdc.com.br. 2021070101 10800 900 1296000 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0