Apex domains cannot have CNAME records.
Question and response
Question
dig smoothlines.store. NS
Answer
smoothlines.store. 5 NS ns1.smoothlines.store.
smoothlines.store. 5 NS ns2.smoothlines.store.
Authority
The response has no authority records.
Additional
ns1.smoothlines.store. 5 A 107.150.19.109
ns2.smoothlines.store. 5 A 107.150.19.11
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0