Apex domains cannot have CNAME records.
Question and response
Question
dig NPORT.RU. NS
Answer
nport.ru. 1 NS ns2.snparking.RU.
nport.ru. 1 NS ns1.snparking.RU.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0