Apex domains cannot have CNAME records.
Question and response
Question
dig webexchange.nu. NS
Answer
webexchange.nu. 5 NS ns2.wannafind.dk.
webexchange.nu. 5 NS ns.wannafind.dk.
Authority
The response has no authority records.
Additional
ns.wannafind.dk. 5 A 185.25.141.6
ns2.wannafind.dk. 5 A 91.197.248.69
ns.wannafind.dk. 5 AAAA 2a02:2339:4006:103:1c:3f6d:daba:dee
ns2.wannafind.dk. 5 AAAA 2a02:2339:1:104:0:0:daba:daa
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0