mail.elkdata.ee has no CNAME records.
Question and response
Question
dig mail.elkdata.ee. NS
Answer
The response has no answer records.
Authority
elkdata.ee. 4764 SOA ns.elkdata.ee. hostmaster.ns.elkdata.ee. 2026020501 10800 1800 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0