gateway2.ps.net has no MX records.
Question and response
Question
dig gateway2.ps.net. MX
Answer
The response has no answer records.
Authority
ps.net. 900 SOA nsptc.ps.net. hostmaster.NSPTC.PS.NET.ps.net. 2025022201 7200 1800 1728000 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0