Apex domains cannot have CNAME records.
Question and response
Question
dig amsio.com. NS
Answer
amsio.com. 5 NS ns1.msgc.ac.
amsio.com. 5 NS ns2.msgc.ac.
amsio.com. 5 NS ns3.msgc.cloud.
amsio.com. 5 NS ns4.msgc.cloud.
Authority
The response has no authority records.
Additional
ns1.msgc.ac. 5 A 162.251.34.5
ns2.msgc.ac. 5 A 185.77.120.5
ns3.msgc.cloud. 5 A 162.248.197.5
ns1.msgc.ac. 5 AAAA 2a03:5500:851:0:0:0:0:5
ns2.msgc.ac. 5 AAAA 2a03:5500:850:0:0:0:0:5
ns3.msgc.cloud. 5 AAAA 2a03:5500:853:0:0:0:0:5
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0