Apex domains cannot have CNAME records.
Question and response
Question
dig hostingserver.nl. NS
Answer
hostingserver.nl. 4 NS ns3.dn-s.eu.
hostingserver.nl. 4 NS ns2.dn-s.be.
hostingserver.nl. 4 NS ns1.dn-s.nl.
hostingserver.nl. 4 NS ns4.dn-s.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0