aa.sc.efscloud.net has no MX records.
Question and response
Question
dig aa.sc.efscloud.net. MX
Answer
The response has no answer records.
Authority
aa.sc.efscloud.net. 600 SOA ns1.efscloud.net. root.efscloud.net. 1651246721 3600 900 3600000 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0