Apex domains cannot have CNAME records.
Question and response
Question
dig mailsecure.in. NS
Answer
mailsecure.in. 5 NS dns3.tatacommunicationsdns.com.
mailsecure.in. 5 NS dns2.tatacommunicationsdns.com.
mailsecure.in. 5 NS dns4.tatacommunicationsdns.com.
mailsecure.in. 5 NS dns1.tatacommunicationsdns.com.
mailsecure.in. 5 NS dns5.tatacommunicationsdns.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0