mail0.presscloud.com has no CNAME records.
Question and response
Question
dig mail0.presscloud.com. NS
Answer
The response has no answer records.
Authority
presscloud.com. 1020 SOA carl.ns.cloudflare.com. dns.cloudflare.com. 2396796662 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0