Apex domains cannot have CNAME records.
Question and response
Question
dig radionet.com.ua. NS
Answer
radionet.com.ua. 5 NS ns2.radionet.com.ua.
radionet.com.ua. 5 NS ns1.radionet.com.ua.
Authority
The response has no authority records.
Additional
ns1.radionet.com.ua. 5 A 195.34.204.11
ns2.radionet.com.ua. 5 A 195.34.204.7
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0