Apex domains cannot have CNAME records.
Question and response
Question
dig merlin.ua. NS
Answer
merlin.ua. 1 NS ns.merlin.ua.
merlin.ua. 1 NS ns.secondary.net.ua.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0