Apex domains cannot have CNAME records.
Question and response
Question
dig bizzup.ru. NS
Answer
bizzup.ru. 5 NS ns18.hostia.name.
bizzup.ru. 5 NS ns17.hostia.name.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0