Apex domains cannot have CNAME records.
Question and response
Question
dig akastream2.com. NS
Answer
akastream2.com. 5 NS a3-64.akam.net.
akastream2.com. 5 NS a4-65.akam.net.
akastream2.com. 5 NS a1-98.akam.net.
akastream2.com. 5 NS a13-65.akam.net.
akastream2.com. 5 NS a12-65.akam.net.
akastream2.com. 5 NS a2-64.akam.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0