Apex domains cannot have CNAME records.
Question and response
Question
dig LEALTA.RU. NS
Answer
LEALTA.RU. 5 NS ns1.tut.net.
LEALTA.RU. 5 NS ns2.tut.net.
Authority
The response has no authority records.
Additional
ns1.tut.net. 5 A 95.131.144.34
ns2.tut.net. 5 A 89.207.216.74
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0