mail2.hem.net has no CNAME records.
Question and response
Question
dig mail2.hem.net. NS
Answer
The response has no answer records.
Authority
hem.net. 1253 SOA dns1.hem.net. hostmaster.hem.net. 2025021401 7200 1800 604800 7200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0