Apex domains cannot have CNAME records.
Question and response
Question
dig ABCTEL.RU. NS
Answer
ABCTEL.RU. 3 NS ns11.hoster.RU.
ABCTEL.RU. 3 NS ns10.hoster.RU.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0