mx2.zeptomail.ca has no CNAME records.
Question and response
Question
dig mx2.zeptomail.ca. NS
Answer
The response has no answer records.
Authority
zeptomail.ca. 600 SOA ns1.zohocorp.com. dnsadmin.vtitan.com. 2026020700 7200 1800 1209600 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0