0.49.138.202.core.vocus.network has no CNAME records.
Question and response
Question
dig 0.49.138.202.core.vocus.network. NS
Answer
The response has no answer records.
Authority
vocus.network. 10800 SOA ns1.vocus.network. root.vocus.network. 2026030201 10800 3600 604800 86420
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0