Apex domains cannot have CNAME records.
Question and response
Question
dig topbrandca.com. NS
Answer
topbrandca.com. 4 NS ns1.topbrandca.com.
topbrandca.com. 4 NS ns2.topbrandca.com.
Authority
The response has no authority records.
Additional
ns1.topbrandca.com. 4 A 63.143.46.162
ns2.topbrandca.com. 4 A 63.143.46.165
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0