Apex domains cannot have CNAME records.
Question and response
Question
dig easynet.nl. NS
Answer
easynet.nl. 5 NS ns3.gtt.net.
easynet.nl. 5 NS ns2.gtt.net.
easynet.nl. 5 NS ns1.gtt.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0