o1.ptr4549.sendgrid.sentia.cloud has no CNAME records.
Question and response
Question
dig o1.ptr4549.sendgrid.sentia.cloud. NS
Answer
The response has no answer records.
Authority
sendgrid.sentia.cloud. 66 SOA ns1.cie.ac. hostmaster.cie.ac. 2022092702 10800 3600 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0