Apex domains cannot have CNAME records.
Question and response
Question
dig brunet.BN. NS
Answer
brunet.BN. 4 NS pt02.brunet.BN.
brunet.BN. 4 NS pt01.brunet.BN.
Authority
The response has no authority records.
Additional
pt01.brunet.bn. 4 A 61.6.254.201
pt02.brunet.bn. 4 A 61.6.254.202
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0