www.srt.com has no MX records.
Question and response
Question
dig www.srt.com. MX
Answer
The response has no answer records.
Authority
srt.com. 10800 SOA ns.minot.com. webmaster.srt.com. 2019060995 10800 3600 10800 10800
Additional
. 0 OPT ; payload 1220, xrcode 0, version 0, flags 0