Apex domains cannot have CNAME records.
Question and response
Question
dig dataclub.eu. NS
Answer
dataclub.eu. 5 NS val.ns.cloudflare.com.
dataclub.eu. 5 NS cash.ns.cloudflare.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0