Apex domains cannot have CNAME records.
Question and response
Question
dig verdonprovence.com. NS
Answer
verdonprovence.com. 5 NS ns-828.awsdns-39.net.
verdonprovence.com. 5 NS ns-1040.awsdns-02.org.
verdonprovence.com. 5 NS ns-610.awsdns-12.net.
verdonprovence.com. 5 NS ns-740.awsdns-28.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0