Apex domains cannot have CNAME records.
Question and response
Question
dig GBLnET.ru. NS
Answer
GBLnET.ru. 3 NS ns.GBLnET.ru.
GBLnET.ru. 3 NS ns2.GBLnET.ru.
Authority
The response has no authority records.
Additional
ns.gblnet.RU. 3 A 95.140.80.1
ns2.gblnet.ru. 3 A 95.140.83.1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0