Apex domains cannot have CNAME records.
Question and response
Question
dig checon.net. NS
Answer
checon.net. 1 NS ns6.checon.de.
checon.net. 1 NS ns.checon.net.
checon.net. 1 NS b.ns14.net.
checon.net. 1 NS ns.ipn.de.
checon.net. 1 NS ns.link-m.de.
Authority
The response has no authority records.
Additional
b.ns14.net. 1 A 217.160.81.160
ns.checon.net. 1 A 194.97.156.2
ns.link-m.de. 1 A 82.135.8.2
b.ns14.net. 1 AAAA 2001:8d8:fe:53:217:160:81:160
ns.link-m.de. 1 AAAA 2001:a60:901e:0:0:0:0:2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0