Apex domains cannot have CNAME records.
Question and response
Question
dig g-portal.se. NS
Answer
g-portal.se. 5 NS elma.ns.cloudflare.com.
g-portal.se. 5 NS graham.ns.cloudflare.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0