Apex domains cannot have CNAME records.
Question and response
Question
dig engelhardt-link.com. NS
Answer
engelhardt-link.com. 5 NS ns-1804.awsdns-33.co.uk.
engelhardt-link.com. 5 NS ns-1023.awsdns-63.net.
engelhardt-link.com. 5 NS ns-213.awsdns-26.com.
engelhardt-link.com. 5 NS ns-1552.awsdns-02.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0