Apex domains cannot have CNAME records.
Question and response
Question
dig fm. NS
Answer
fm. 5 NS d.nic.fm.
fm. 5 NS f.nic.fm.
fm. 5 NS a.nic.fm.
fm. 5 NS c.nic.fm.
fm. 5 NS b.nic.fm.
fm. 5 NS e.nic.fm.
Authority
The response has no authority records.
Additional
a.nic.fm. 121776 A 194.169.218.26
b.nic.fm. 121776 A 185.24.64.26
c.nic.fm. 121776 A 212.18.248.26
d.nic.fm. 121776 A 212.18.249.26
e.nic.fm. 164646 A 204.61.216.137
f.nic.fm. 172491 A 206.51.254.3
a.nic.fm. 121776 AAAA 2001:67c:13cc:0:0:0:1:26
b.nic.fm. 121776 AAAA 2a04:2b00:13cc:0:0:0:1:26
c.nic.fm. 121776 AAAA 2a04:2b00:13ee:0:0:0:0:26
d.nic.fm. 121776 AAAA 2a04:2b00:13ff:0:0:0:0:26
e.nic.fm. 164646 AAAA 2001:500:14:6137:ad:0:0:1
f.nic.fm. 172491 AAAA 2620:171:804:ad2:0:0:0:3
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0