Apex domains cannot have CNAME records.
Question and response
Question
dig agustinperegrin.com. NS
Answer
agustinperegrin.com. 5 NS ns1.agustinperegrin.com.
agustinperegrin.com. 5 NS ns2.agustinperegrin.com.
Authority
The response has no authority records.
Additional
ns1.agustinperegrin.com. 5 A 64.113.9.129
ns2.agustinperegrin.com. 5 A 62.112.8.225
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0