Apex domains cannot have CNAME records.
Question and response
Question
dig emea.sabacloud.com. NS
Answer
emea.sabacloud.com. 5 NS ns4.p05.dynect.net.
emea.sabacloud.com. 5 NS ns1.p05.dynect.net.
emea.sabacloud.com. 5 NS ns2.p05.dynect.net.
emea.sabacloud.com. 5 NS ns3.p05.dynect.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0