Apex domains cannot have CNAME records.
Question and response
Question
dig coloclue.net. NS
Answer
coloclue.net. 4 NS ns5.coloclue.net.
coloclue.net. 4 NS ns0.coloclue.net.
Authority
The response has no authority records.
Additional
ns0.coloclue.net. 4 A 94.142.247.18
ns5.coloclue.net. 4 A 194.1.163.186
ns0.coloclue.net. 4 AAAA 2a02:898:0:200:0:0:1:53
ns5.coloclue.net. 4 AAAA 2001:678:d78:b:0:0:8:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0