dnsus1.accellion.com has no MX records.
Question and response
Question
dig dnsus1.accellion.com. MX
Answer
The response has no answer records.
Authority
accellion.com. 60 SOA dnsma.accellion.com. root.mail.accellion.com. 2025092500 28800 7200 604800 60
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0