smtp45.allytech.com has no CNAME records.
Question and response
Question
dig smtp45.allytech.com. NS
Answer
The response has no answer records.
Authority
allytech.com. 2779 SOA ns1.dnscheck.com.ar. root.allytech.com. 2025091105 3600 10800 604800 7200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0