Apex domains cannot have CNAME records.
Question and response
Question
dig ipnet.kiev.ua. NS
Answer
ipnet.kiev.ua. 5 NS ns1.ip.net.ua.
ipnet.kiev.ua. 5 NS ns2.ip.net.ua.
Authority
The response has no authority records.
Additional
ns1.ip.net.ua. 5 A 193.0.220.34
ns2.ip.net.ua. 5 A 195.64.148.34
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0