We just bought your module Minimum Order Amount for Magento 2 v1.1.1 for my Magento 2.1.18 and it works fine.
However, when I try to go to the sales -> sales in the CMS I am getting a full blank page.
Please let us know how to fix it?
This issue happens since on Magento M2.1.18 doesn't have class Serialize.
To resolve this issue, please download the attached file and overwrite the current file on your site.