_dmarc.eserver.net has no CNAME records.
Question and response
Question
dig _dmarc.eserver.net. NS
Answer
The response has no answer records.
Authority
eserver.net. 668 SOA ns1.eserver.net. hostmaster.eserver.sk. 2026012901 7200 3600 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0