smtp.myfibermail.com has no CNAME records.
Question and response
Question
dig smtp.myfibermail.com. NS
Answer
The response has no answer records.
Authority
myfibermail.com. 10800 SOA ns1.epbinternet.com. poc.epbinternet.com. 2026022001 10802 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0