Apex domains cannot have CNAME records.
Question and response
Question
dig ikoula.net. NS
Answer
ikoula.net. 4 NS paul.ns.ikoula.com.
ikoula.net. 4 NS laura.ns.ikoula.com.
ikoula.net. 4 NS tristan.ns.ikoula.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0