Apex domains cannot have CNAME records.
Question and response
Question
dig dace.be. NS
Answer
dace.be. 5 NS ns.zxcs.be.
dace.be. 5 NS ns.zxcs.eu.
dace.be. 5 NS ns.zxcs.nl.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0