Apex domains cannot have CNAME records.
Question and response
Question
dig dds.eu. NS
Answer
dds.eu. 5 NS ns1.dds.nl.
dds.eu. 5 NS ns2.dds.eu.
dds.eu. 5 NS ns3.dds.amsterdam.
Authority
The response has no authority records.
Additional
ns1.dds.nl. 5 A 141.255.180.130
ns2.dds.eu. 5 A 136.144.233.156
ns3.dds.amsterdam. 5 A 85.158.250.40
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0