mail.orleur.biz has no NS records.
NS records for this zone are defined at orleur.biz.
NS records for this zone are defined at orleur.biz.
Question and response
Question
dig mail.orleur.biz. NS
Answer
The response has no answer records.
Authority
orleur.biz. 3601 SOA dns1.registrar-servers.com. hostmaster.registrar-servers.com. 1772017954 43200 3600 604800 3601
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0