mail.fxrm.com has no CNAME records.
Question and response
Question
dig mail.fxrm.com. NS
Answer
The response has no answer records.
Authority
fxrm.com. 3600 SOA ns0.fxrm.com. admin.fxrm.com. 2026022301 1400 7200 86400 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0