ns1.switch.com has no MX records.
Question and response
Question
dig ns1.switch.com. MX
Answer
The response has no answer records.
Authority
switch.com. 3600 SOA ns1.switch.com. hostmaster.switch.com. 2026021202 10800 900 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0