Apex domains cannot have CNAME records.
Question and response
Question
dig NVHOST.RU. NS
Answer
NVHOST.RU. 5 NS vps.NVHOST.RU.
NVHOST.RU. 5 NS ns.NVHOST.RU.
Authority
The response has no authority records.
Additional
ns.nvhost.ru. 5 A 185.87.194.251
vps.nvhost.ru. 5 A 91.199.149.47
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0