mail.busum.net has no NS records.
NS records for this zone are defined at busum.net.
NS records for this zone are defined at busum.net.
Question and response
Question
dig mail.busum.net. NS
Answer
The response has no answer records.
Authority
busum.net. 120 SOA ns2.busum.net. root.ns3008652.ip-149-202-66.eu. 2026030403 3600 300 3600 180
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0