91-133-32-0.ip.flexfonenet.dk has no NS records.
NS records for this zone are defined at ip.flexfonenet.dk.
NS records for this zone are defined at ip.flexfonenet.dk.
Question and response
Question
dig 91-133-32-0.ip.flexfonenet.dk. NS
Answer
The response has no answer records.
Authority
ip.flexfonenet.dk. 86400 SOA auth01.dns.sippeer.dk. hostmaster.flexfone.dk. 2016111101 28800 7200 604800 86400
Additional
. 0 OPT ; payload 1680, xrcode 0, version 0, flags 0