mx10.atmosphere.sg.group-ib.com has no MX records.
Question and response
Question
dig a4426521437ad42b6baedae66b7f2092-62529caf5ab986d6.elb.ap-southeast-1.amazonaws.com. MX
Answer
The response has no answer records.
Authority
elb.ap-southeast-1.amazonaws.com. 60 SOA ns-448.awsdns-56.com. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 60
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0