vmx.spamcop.net has no CNAME records.
Question and response
Question
dig vmx.spamcop.net. NS
Answer
The response has no answer records.
Authority
spamcop.net. 300 SOA ns1-93.akam.net. hostmaster.akamai.com. 2024060402 300 300 300 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0