Apex domains cannot have CNAME records.
Question and response
Question
dig futureweb.org. NS
Answer
futureweb.org. 4 NS ns2.futureweb.at.
futureweb.org. 4 NS ns3.futureweb.at.
futureweb.org. 4 NS ns1.futureweb.at.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0