Apex domains cannot have CNAME records.
Question and response
Question
dig in.ua. NS
Answer
in.ua. 5 NS ns.in.ua.
in.ua. 5 NS nn.ns.ua.
in.ua. 5 NS cz.ns.ua.
in.ua. 5 NS ho1.ns.od.ua.
Authority
The response has no authority records.
Additional
cz.ns.ua. 172117 A 185.43.134.15
nn.ns.ua. 172117 A 194.58.197.4
ns.in.ua. 5 A 167.99.46.217
cz.ns.ua. 172117 AAAA 2001:148f:fffd:0:0:0:0:15
nn.ns.ua. 172117 AAAA 2a01:3f1:c001:0:0:0:0:53
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0