Attempt to add delivery address ends in ERP transport error.

Prereq.: ERP config is set up in application. Existing business customer has been imported to application.

Steps:

1. On frontend log in as business customer.
2. Go to My Account.
3. Click on Add Address under Your delivery addresses (screen 1).
4. Fill in customer data matching ERP data (screen 2).
5. Click Save address.

Actual result: Address is not saved, error occurs The response of the ERP transport is not valid.. Details of error response are attached.
Expected result: Address is saved and available on frontend and in back-office.