When you import Amazon orders you receive an error
11:40:53 AmazonSC: Retrieving Amazon order information...
11:40:53 AmazonSC: Requested report type is deprecated in MWS [InvalidParameterValue:Sender]
11:40:53 AmazonSC: Amazon logon error. Run Failed.
Amazon has stopped allowing One Stop Order Processing access to orders using the existing approach (MWS). One Stop Order Processing has not changed and this is out of our control and has been a decision by Amazon. You can use your own Private Amazon Developer ID, if you have the relevant permissions.
You can import orders using an additional (free) App and One Stop Order Processing will work in the same way as it previously did. To set this up you should use the following guide:
Using One Stop Order Processing with Amazon Merchant Transport Utility (AMTU)
Alternatively, if you are using Shopify you can process all of your Amazon orders through Shopify using One Stop Order Processing. There is more information on this at:
Amazon by CedCommerce