Apex domains cannot have CNAME records.
Question and response
Question
dig proxi.nl. NS
Answer
proxi.nl. 5 NS dns2.proxi.nl.
proxi.nl. 5 NS dns1.proxi.nl.
Authority
The response has no authority records.
Additional
dns1.proxi.nl. 5 A 89.149.192.4
dns2.proxi.nl. 5 A 89.149.192.56
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0