Apex domains cannot have CNAME records.
Question and response
Question
dig colocall.net. NS
Answer
colocall.net. 5 NS ns1.colocall.net.
colocall.net. 5 NS ns2.colocall.net.
colocall.net. 5 NS ns1.colocall.eu.
Authority
The response has no authority records.
Additional
ns1.colocall.eu. 5 A 195.168.46.118
ns1.colocall.net. 5 A 62.149.2.59
ns2.colocall.net. 5 A 216.66.94.157
ns1.colocall.net. 5 AAAA 2a03:6300:0:0:0:0:0:53
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0