Apex domains cannot have CNAME records.
Question and response
Question
dig inet.ns01.eu. NS
Answer
inet.ns01.eu. 5 NS d.ns14.net.
inet.ns01.eu. 5 NS a.ns14.net.
inet.ns01.eu. 5 NS b.ns14.net.
inet.ns01.eu. 5 NS c.ns14.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0