Apex domains cannot have CNAME records.
Question and response
Question
dig one.iamemonline.com. NS
Answer
one.iamemonline.com. 5 NS ns1.onesrv.iamemonline.com.
one.iamemonline.com. 5 NS ns2.onesrv.iamemonline.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0