Apex domains cannot have CNAME records.
Question and response
Question
dig d1qa6fi3c1lo86.cloudfront.net. NS
Answer
d1qa6fi3c1lo86.cloudfront.net. 5 NS ns-1857.awsdns-40.co.uk.
d1qa6fi3c1lo86.cloudfront.net. 5 NS ns-922.awsdns-51.net.
d1qa6fi3c1lo86.cloudfront.net. 5 NS ns-145.awsdns-18.com.
d1qa6fi3c1lo86.cloudfront.net. 5 NS ns-1343.awsdns-39.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0