unassigned.ams.resource.cloud has no MX records.
Question and response
Question
dig unassigned.ams.resource.cloud. MX
Answer
The response has no answer records.
Authority
ams.resource.cloud. 3600 SOA ns2.ams.teamblue.cloud. hostmaster.teamblue.cloud. 1771916771 3582 600 86400 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0