Apex domains cannot have CNAME records.
Question and response
Question
dig pvgsb.com. NS
Answer
pvgsb.com. 5 NS ns-547.awsdns-04.net.
pvgsb.com. 5 NS ns-1006.awsdns-61.net.
pvgsb.com. 5 NS ns-881.awsdns-46.net.
pvgsb.com. 5 NS ns-1493.awsdns-58.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0