mail.outfrontps.com has no CNAME records.
Question and response
Question
dig mail.outfrontps.com. NS
Answer
The response has no answer records.
Authority
outfrontps.com. 216 SOA ns39.domaincontrol.com. dns.jomax.net. 2024091901 28800 7200 604800 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0