smtpin2.zoho.com has no CNAME records.
Question and response
Question
dig smtpin2.zoho.com. NS
Answer
The response has no answer records.
Authority
zoho.com. 300 SOA ns1.zohocorp.com. dnsadmin.vtitan.com. 2026030603 7200 1800 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0