Apex domains cannot have CNAME records.
Question and response
Question
dig exact.nl. NS
Answer
exact.nl. 4 NS ns-585.awsdns-09.net.
exact.nl. 4 NS ns-446.awsdns-55.com.
exact.nl. 4 NS ns-1955.awsdns-52.co.uk.
exact.nl. 4 NS ns-1477.awsdns-56.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0