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