Apex domains cannot have CNAME records.
Question and response
Question
dig acom-sacom-bouches-du-rhone.com. NS
Answer
acom-sacom-bouches-du-rhone.com. 5 NS ns2.acom-sacom-bouches-du-rhone.com.
acom-sacom-bouches-du-rhone.com. 5 NS ns1.acom-sacom-bouches-du-rhone.com.
Authority
The response has no authority records.
Additional
ns1.acom-sacom-bouches-du-rhone.com. 5 A 194.180.37.161
ns2.acom-sacom-bouches-du-rhone.com. 5 A 37.59.150.248
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0