ns2.hk.eserver.net has no MX records.
Question and response
Question
dig ns2.hk.eserver.net. MX
Answer
The response has no answer records.
Authority
hk.eserver.net. 600 SOA ns1.hk.eserver.net. hostmaster.hk.eserver.net. 2025082501 1080 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0