ns23.cloudsouth.net has no CNAME records.
Question and response
Question
dig ns23.cloudsouth.net. NS
Answer
The response has no answer records.
Authority
cloudsouth.net. 3600 SOA NS9.WORLDNIC.COM. namehost.WORLDNIC.COM. 122111415 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0