Apex domains cannot have CNAME records.
Question and response
Question
dig as8218.eu. NS
Answer
as8218.eu. 5 NS ns60.zayo.com.
as8218.eu. 5 NS ns50.zayo.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0