Apex domains cannot have CNAME records.
Question and response
Question
dig shoppinginrotterdam.com. NS
Answer
shoppinginrotterdam.com. 5 NS ns1.shoppinginrotterdam.com.
shoppinginrotterdam.com. 5 NS ns2.shoppinginrotterdam.com.
Authority
The response has no authority records.
Additional
ns1.shoppinginrotterdam.com. 5 A 96.47.162.166
ns2.shoppinginrotterdam.com. 5 A 51.161.21.79
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0