Apex domains cannot have CNAME records.
Question and response
Question
dig mutlusirinler.com. NS
Answer
mutlusirinler.com. 5 NS ns-1986.awsdns-56.co.uk.
mutlusirinler.com. 5 NS ns-1357.awsdns-41.org.
mutlusirinler.com. 5 NS ns-1146.awsdns-15.org.
mutlusirinler.com. 5 NS ns-1747.awsdns-26.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0