ns1.iristransport.com has no MX records.
Question and response
Question
dig ns1.iristransport.net. MX
Answer
The response has no answer records.
Authority
iristransport.net. 900 SOA ns1.iristransport.net. hostmaster.iristransport.net. 2021120100 10800 15 604800 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0