Apex domains cannot have CNAME records.
Question and response
Question
dig partoo.fr. NS
Answer
partoo.fr. 5 NS ns-996.awsdns-60.net.
partoo.fr. 5 NS ns-1339.awsdns-39.org.
partoo.fr. 5 NS ns-1544.awsdns-01.co.uk.
partoo.fr. 5 NS ns-272.awsdns-34.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0