Apex domains cannot have CNAME records.
Question and response
Question
dig hiperonline.com.tr. NS
Answer
hiperonline.com.tr. 5 NS ns1.hiperonline.com.tr.
hiperonline.com.tr. 5 NS ns2.hiperonline.com.tr.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0