sender.zohobooks.com has no CNAME records.
Question and response
Question
dig sender.zohobooks.com. NS
Answer
The response has no answer records.
Authority
zohobooks.com. 600 SOA ns1.zohocorp.com. dnsadmin.vtitan.com. 2026030701 7200 1800 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0