Apex domains cannot have CNAME records.
Question and response
Question
dig gamepool.pro. NS
Answer
gamepool.pro. 2 NS ns2.gamepool.pro.
gamepool.pro. 2 NS ns1.gamepool.pro.
Authority
The response has no authority records.
Additional
ns1.gamepool.pro. 2 A 86.111.188.134
ns2.gamepool.pro. 2 A 51.38.144.212
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0