Apex domains cannot have CNAME records.
Question and response
Question
dig orbit.teamleader.eu. NS
Answer
orbit.teamleader.eu. 5 NS ns-819.awsdns-38.net.
orbit.teamleader.eu. 5 NS ns-1493.awsdns-58.org.
orbit.teamleader.eu. 5 NS ns-1810.awsdns-34.co.uk.
orbit.teamleader.eu. 5 NS ns-51.awsdns-06.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0