mxn.mxhichina.com has no MX records.
Question and response
Question
dig mxn.mxhichina.com. MX
Answer
The response has no answer records.
Authority
mxhichina.com. 600 SOA dns1.hichina.com. hostmaster.hichina.com. 2026010913 3600 1200 86400 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0