Apex domains cannot have CNAME records.
Question and response
Question
dig clickdimensions.com. NS
Answer
clickdimensions.com. 3 NS pdns13.domaincontrol.com.
clickdimensions.com. 3 NS pdns14.domaincontrol.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0