authns2.lumen.tech has no MX records.
Question and response
Question
dig authns2.lumen.tech. MX
Answer
The response has no answer records.
Authority
lumen.tech. 300 SOA authns1.qwest.net. abuse.aup.lumen.com. 2251209000 10800 3600 604800 300
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0