schedule.isp.net has no NS records.
NS records for this zone are defined at isp.net.
NS records for this zone are defined at isp.net.
Question and response
Question
dig schedule.isp.net. NS
Answer
The response has no answer records.
Authority
isp.net. 3600 SOA gate.lasvegas.net. postmaster.lasvegas.net. 2025121616 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0