Apex domains cannot have CNAME records.
Question and response
Question
dig teamworkdesk.com. NS
Answer
teamworkdesk.com. 5 NS ns-1573.awsdns-04.co.uk.
teamworkdesk.com. 5 NS ns-186.awsdns-23.com.
teamworkdesk.com. 5 NS ns-815.awsdns-37.net.
teamworkdesk.com. 5 NS ns-1466.awsdns-55.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0