If you are exporting orders to a fulfillment center, some or all of your orders coming from Amazon and Amazon Seller Central may not export to your fulfillment center.
Cause
A payment method is required for the order for the fulfillment center export routine to run properly. Amazon orders will most likely not have a payment method
Solution
Go to [Set System Parameters]. Browse to the Amazon group. Find the parameter "AmazonPaymentMethod". Set this parameter to a generic payment method of your choice, for example, "Generic1".
From this point forward all Amazon orders which do not have a payment method will be assigned the payment method that you select and the fulfillment export process will run successfully.