net.kh has no MX records.
Question and response
Question
dig net.kh. MX
Answer
The response has no answer records.
Authority
net.kh. 10800 SOA ns1.dns.net.kh. www.trc.gov.kh. 2025050540 7200 3600 2419200 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0