Apex domains cannot have CNAME records.
Question and response
Question
dig skyviewonline.com. NS
Answer
skyviewonline.com. 4 NS ns2.bdinfotech.xyz.
skyviewonline.com. 4 NS ns1.bdinfotech.xyz.
Authority
The response has no authority records.
Additional
ns1.bdinfotech.xyz. 5 A 216.194.168.112
ns2.bdinfotech.xyz. 5 A 70.39.146.236
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0