Apex domains cannot have CNAME records.
Question and response
Question
dig marincomp.com. NS
Answer
marincomp.com. 1 NS ns-1821.awsdns-35.co.uk.
marincomp.com. 1 NS ns-1862.awsdns-40.co.uk.
marincomp.com. 1 NS ns-490.awsdns-61.com.
marincomp.com. 1 NS ns-680.awsdns-21.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0