Apex domains cannot have CNAME records.
Question and response
Question
dig agentil.net. NS
Answer
agentil.net. 2 NS ns-54-a.gandi.net.
agentil.net. 2 NS ns-240-c.gandi.net.
agentil.net. 2 NS ns-101-b.gandi.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0