Apex domains cannot have CNAME records.
Question and response
Question
dig deir.info. NS
Answer
deir.info. 5 NS ns1.deir.info.
deir.info. 5 NS ns2.deir.info.
Authority
The response has no authority records.
Additional
ns1.deir.info. 5 A 149.50.96.18
ns2.deir.info. 5 A 149.50.99.137
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0