bb-nbdb.gblnet.net has no CNAME records.
Question and response
Question
dig bb-nbdb.gblnet.net. NS
Answer
The response has no answer records.
Authority
gblnet.net. 4868 SOA ns.gblnet.net. vvv.gblnet.net. 2026022701 10800 1200 1209600 259200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0