Apex domains cannot have CNAME records.
Question and response
Question
dig riotactguild.com. NS
Answer
riotactguild.com. 5 NS ns2.riotactguild.com.
riotactguild.com. 5 NS ns1.riotactguild.com.
Authority
The response has no authority records.
Additional
ns1.riotactguild.com. 5 A 144.217.162.99
ns2.riotactguild.com. 5 A 51.161.91.47
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0