Apex domains cannot have CNAME records.
Question and response
Question
dig GBLnet.RU. NS
Answer
GBlNeT.ru. 2 NS ns2.GBLnet.RU.
GBlNeT.ru. 2 NS ns.GBLnet.RU.
Authority
The response has no authority records.
Additional
ns.gblnet.RU. 2 A 95.140.80.1
ns2.gblnet.ru. 2 A 95.140.83.1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0