mail.negociagb.com.br has no NS records.
NS records for this zone are defined at negociagb.com.br.
NS records for this zone are defined at negociagb.com.br.
Question and response
Question
dig mail.negociagb.com.br. NS
Answer
The response has no answer records.
Authority
negociagb.com.br. 1800 SOA kim.ns.cloudflare.com. dns.cloudflare.com. 2397607831 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0