mail.yipi.com.br has no NS records.
NS records for this zone are defined at yipi.com.br.
NS records for this zone are defined at yipi.com.br.
Question and response
Question
dig mail.yipi.com.br. NS
Answer
The response has no answer records.
Authority
yipi.com.br. 3600 SOA ns1.yipi.com.br. admin.yipi.com.br. 2025123100 3600 7200 1209600 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0