mailserver.avisomensagem.com.br has no NS records.
NS records for this zone are defined at avisomensagem.com.br.
NS records for this zone are defined at avisomensagem.com.br.
Question and response
Question
dig mailserver.avisomensagem.com.br. NS
Answer
The response has no answer records.
Authority
avisomensagem.com.br. 1800 SOA kim.ns.cloudflare.com. dns.cloudflare.com. 2398068594 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0