Apex domains cannot have CNAME records.
Question and response
Question
dig dscb.akamai.net. NS
Answer
dscb.akamai.net. 5 NS n5dscb.akamai.net.
dscb.akamai.net. 5 NS n0dscb.akamai.net.
dscb.akamai.net. 5 NS n7dscb.akamai.net.
dscb.akamai.net. 5 NS n6dscb.akamai.net.
dscb.akamai.net. 5 NS n1dscb.akamai.net.
dscb.akamai.net. 5 NS n2dscb.akamai.net.
dscb.akamai.net. 5 NS n4dscb.akamai.net.
dscb.akamai.net. 5 NS n3dscb.akamai.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0