Apex domains cannot have CNAME records.
Question and response
Question
dig ns-1.xetnet.com. NS
Answer
ns-1.xetnet.com. 3 NS ns-2.xetnet.com.
ns-1.xetnet.com. 3 NS ns-1.xetnet.com.
Authority
The response has no authority records.
Additional
ns-1.xetnet.com. 1 A 95.175.122.193
ns-2.xetnet.com. 1 A 62.106.45.33
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0