I'm trying to setup SAML with NAM as the IDP and SimpleSAML functioning
as the SP. I've imported the metadata from the SP into NAM as a SAML2
Trusted Provider.

I've tested the SP using OpenIDP and that seems to be functioning, I can
get the SimpleSAML SP to authenticate using the OpenIDP.

When trying to use the NAM as the IDP, I get an error -

Error:Unable to complete request at this time. (Request was from an
untrusted provider-DAD5123875EB9079)

Looking at the catalina.out I see an error -

Warning: Invalid resource key: Request was from an untrusted provider.
No prefix!

I've added the SP into NAM and the metadata is the same as the one that
works with OpenIDP so am unsure where its breaking. Does anyone have any