Apex domains cannot have CNAME records.
Question and response
Question
dig ic3.com. NS
Answer
ic3.com. 5 NS a9-64.akam.net.
ic3.com. 5 NS a2-65.akam.net.
ic3.com. 5 NS melinda.ns.cloudflare.com.
ic3.com. 5 NS a10-64.akam.net.
ic3.com. 5 NS lloyd.ns.cloudflare.com.
ic3.com. 5 NS a1-190.akam.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0