Apex domains cannot have CNAME records.
Question and response
Question
dig pakt.spb.ru. NS
Answer
pakt.spb.ru. 5 NS adns2.pakt.ru.
pakt.spb.ru. 5 NS ns1.edgedns.ru.
pakt.spb.ru. 5 NS ns2.edgedns.world.
pakt.spb.ru. 5 NS adns1.pakt.ru.
Authority
The response has no authority records.
Additional
adns1.pakt.ru. 5 A 217.78.230.83
adns2.pakt.ru. 5 A 5.8.38.1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0