Access FBA Shipment Items - EU

[defenderjim]

I have SP-API code which can access FBA Shipments and their items in the US, where my account is based.
My app is self-signed and will never be on the Amazon Marketplace.

Using my account, for the EU marketplace, I am able to list FBA Shipments, but not their items. Where as this is successful for North America.

I get this response:
"The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel."

Why is that?