Apex domains cannot have CNAME records.
Question and response
Question
dig vaal.cv.ua. NS
Answer
vaal.cv.ua. 3 NS ns2.ukrnames.com.
vaal.cv.ua. 3 NS ns3.ukrnames.com.
vaal.cv.ua. 3 NS ns1.ukrnames.com.
Authority
The response has no authority records.
Additional
ns1.ukrnames.com. 5 A 104.131.20.233
ns2.ukrnames.com. 5 A 195.123.192.2
ns3.ukrnames.com. 5 A 37.59.88.192
ns1.ukrnames.com. 5 AAAA 2604:a880:800:10:0:0:68:2001
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0