41.131.252.185.rev.airmob.eu has no MX records.
Question and response
Question
dig 41.131.252.185.rev.airmob.eu. MX
Answer
The response has no answer records.
Authority
131.252.185.rev.airmob.eu. 86400 SOA rdns1.airmob.eu. hostmaster.airmob.net. 202509100 14400 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0