Apex domains cannot have CNAME records.
Question and response
Question
dig mps.fi. NS
Answer
mps.fi. 5 NS ns10.prewise.com.
mps.fi. 5 NS ns1.prewise.com.
mps.fi. 5 NS ns4.prewise.com.
Authority
The response has no authority records.
Additional
ns1.prewise.com. 5 A 185.87.245.10
ns10.prewise.com. 5 A 20.127.53.67
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0