192.192-255.40.172.209.in-addr.arpa has no NS records.
NS records for this zone are defined at 192-255.40.172.209.in-addr.arpa.
NS records for this zone are defined at 192-255.40.172.209.in-addr.arpa.
Question and response
Question
dig 192.192-255.40.172.209.in-addr.arpa. NS
Answer
The response has no answer records.
Authority
192-255.40.172.209.in-addr.arpa. 180 SOA nsm0.tckops.net. admin.tckops.net. 2017081114 14400 900 1209600 180
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0