Apex domains cannot have CNAME records.
Question and response
Question
dig kgm.se. NS
Answer
kgm.se. 4 NS ns-702.awsdns-23.net.
kgm.se. 4 NS ns-1042.awsdns-02.org.
kgm.se. 4 NS ns-1973.awsdns-54.co.uk.
kgm.se. 4 NS ns-274.awsdns-34.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0