relay.tetrain.com has no MX records.
Question and response
Question
dig relay.tetrain.com. MX
Answer
The response has no answer records.
Authority
tetrain.com. 600 SOA ns39.domaincontrol.com. dns.jomax.net. 2026011300 28800 7200 604800 600
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0