dns.amatukami.net has no MX records.
Question and response
Question
dig dns.amatukami.net. MX
Answer
The response has no answer records.
Authority
amatukami.net. 3600 SOA dns.amatukami.net. hostmaster.amatukami.net. 1540297737 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0