mail.infobunker.com has no MX records.
Question and response
Question
dig mail.infobunker.com. MX
Answer
The response has no answer records.
Authority
infobunker.com. 3600 SOA ns1.infobunker.com. hostmaster.infobunker.com. 2025121701 28800 7200 2419200 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0