Apex domains cannot have CNAME records.
Question and response
Question
dig oneliner.be. NS
Answer
oneliner.be. 5 NS dns2.iwantmyname.com.
oneliner.be. 5 NS dns3.iwantmyname.com.
oneliner.be. 5 NS dns1.iwantmyname.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0