Apex domains cannot have CNAME records.
Question and response
Question
dig unoeuro.com. NS
Answer
unoeuro.com. 5 NS ns2.simply.com.
unoeuro.com. 5 NS ns1.simply.com.
unoeuro.com. 5 NS ns3.simply.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0