dns2.shop-pro.jp has no MX records.
Question and response
Question
dig dns2.shop-pro.jp. MX
Answer
The response has no answer records.
Authority
shop-pro.jp. 600 SOA dns1.shop-pro.jp. admin.pepabo.com. 2010728521 900 600 604800 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0