mail.sitel.com.br has no NS records.
NS records for this zone are defined at sitel.com.br.
NS records for this zone are defined at sitel.com.br.
Question and response
Question
dig mail.sitel.com.br. NS
Answer
The response has no answer records.
Authority
sitel.com.br. 10800 SOA ns1.sitel.com.br. noc.clicknet.net.br. 2024120401 3600 120 1209600 10800
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0