Apex domains cannot have CNAME records.
Question and response
Question
dig mx1.TIMEWEB.RU. NS
Answer
mx1.TIMEWEB.RU. 5 NS ns3.timeweb.org.
mx1.TIMEWEB.RU. 5 NS ns4.timeweb.org.
mx1.TIMEWEB.RU. 5 NS ns1.TIMEWEB.RU.
mx1.TIMEWEB.RU. 5 NS ns2.TIMEWEB.RU.
Authority
The response has no authority records.
Additional
ns1.TIMEWEB.RU. 5 A 85.193.93.93
ns2.TIMEWEB.RU. 5 A 85.193.93.85
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0