ns20.holhost.com has no CNAME records.
Question and response
Question
dig ns20.holhost.com. NS
Answer
The response has no answer records.
Authority
holhost.com. 10800 SOA ns2.cloud-f51007.managed-vps.net. noc.holhost.com. 2025120433 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0