mailsender.amabis.com has no CNAME records.
Question and response
Question
dig mailsender.amabis.com. NS
Answer
The response has no answer records.
Authority
amabis.com. 3071 SOA ns1.amabis.com. hostmaster.amabis.com. 2019052307 3600 900 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0