Apex domains cannot have CNAME records.
Question and response
Question
dig providesupport.com. NS
Answer
providesupport.com. 2 NS ns-1541.awsdns-00.co.uk.
providesupport.com. 2 NS ns-1327.awsdns-37.org.
providesupport.com. 2 NS ns-426.awsdns-53.com.
providesupport.com. 2 NS ns-677.awsdns-20.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0