AppStream with SSO and Active Directory problem

I've setup AppStream 2.0 using AWS Active Directory as identity provider using the guide below

https://aws.amazon.com/blogs/desktop-and-application-streaming/enable-federation-with-aws-single-sign-on-and-amazon-appstream-2-0/

The application is configured on the SSO portal.

Relay State =
https://appstream2.us-east-1.aws.amazon.com/saml?AppStreamStack1&accountId=xxxxxxxxxxx

I can logon to the SSO portal with AD credentials and am presented with the Appstream icon above.

I get this error every time:
Bad Request.(Error Code: INVALID_RELAY_STATE);Status Code:400

There is very little about this error except that I must have the URL wrong. It would appear the AD authentication part is working (the hard part?)

Any ideas how to troubleshoot?

Found the problem:
https://appstream2.us-east-1.aws.amazon.com/saml?**stack=**AppStreamStack1&accountId=xxxxxxxxxxx

Edited by: stevea3342 on Jun 25, 2021 4:24 PM

Edited by: stevea3342 on Jun 25, 2021 4:33 PM