Apex domains cannot have CNAME records.
Question and response
Question
dig egain.net. NS
Answer
egain.net. 5 NS ns-1059.awsdns-04.org.
egain.net. 5 NS ns-1630.awsdns-11.co.uk.
egain.net. 5 NS ns-291.awsdns-36.com.
egain.net. 5 NS ns-867.awsdns-44.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0