Apex domains cannot have CNAME records.
Question and response
Question
dig ipreverso.com. NS
Answer
ipreverso.com. 2 NS ns91.itmnetworks.net.
ipreverso.com. 2 NS ns93.itmnetworks.net.
ipreverso.com. 2 NS ns92.itmnetworks.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0