ns2.SAMTEL.RU has no CNAME records.
Question and response
Question
dig ns2.SAMTEL.RU. NS
Answer
The response has no answer records.
Authority
samtel.RU. 4288 SOA ns1.samtel.RU. root.samtel.RU. 2026021801 28800 3600 1814400 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0