Apex domains cannot have CNAME records.
Question and response
Question
dig SERVICEPIPE.RU. NS
Answer
servicepipe.ru. 5 NS ns03.servicepipe.ru.
servicepipe.ru. 5 NS dns-02.servicepipe.ru.
servicepipe.ru. 5 NS dns-01.servicepipe.ru.
servicepipe.ru. 5 NS ns04.servicepipe.ru.
Authority
The response has no authority records.
Additional
ns03.servicepipe.ru. 5 A 185.169.154.98
ns04.servicepipe.ru. 5 A 185.169.154.99
dns-01.servicepipe.ru. 5 A 185.66.85.148
dns-02.SERVICEPIPE.RU. 5 A 185.66.85.149
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0