mx15.daldata.net has no CNAME records.
Question and response
Question
dig mx15.daldata.net. NS
Answer
The response has no answer records.
Authority
daldata.net. 1800 SOA jaziel.ns.cloudflare.com. dns.cloudflare.com. 2396407867 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0