mail.cmshigh.com has no CNAME records.
Question and response
Question
dig mail.cmshigh.com. NS
Answer
The response has no answer records.
Authority
cmshigh.com. 5178 SOA ns1.cmshigh.com. cpanel_notice.notifiche.serverplan.com. 2026022101 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0