Apex domains cannot have CNAME records.
Question and response
Question
dig queuemanager.net. NS
Answer
queuemanager.net. 5 NS ns2.queuemanager.net.
queuemanager.net. 5 NS ns1.queuemanager.net.
Authority
The response has no authority records.
Additional
ns1.queuemanager.net. 5 A 157.254.12.79
ns2.queuemanager.net. 5 A 5.181.190.102
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0