Apex domains cannot have CNAME records.
Question and response
Question
dig ampr.org. NS
Answer
ampr.org. 5 NS ns1.de.ardc.net.
ampr.org. 5 NS a.gw4.uk.
ampr.org. 5 NS ns.ardc.net.
ampr.org. 5 NS ns2.us.ardc.net.
Authority
The response has no authority records.
Additional
a.gw4.uk. 5 A 185.53.45.23
ns.ardc.net. 5 A 44.1.1.44
ns1.de.ardc.net. 5 A 192.68.17.12
ns2.us.ardc.net. 5 A 107.161.208.49
a.gw4.uk. 5 AAAA 2a0a:bb00:0:0:0:0:0:17
ns.ardc.net. 5 AAAA 2a0a:bb00:0:44:0:0:0:2c
ns2.us.ardc.net. 5 AAAA 2602:ffd3:0:2:0:0:0:11
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0