SAML with Azure AD setup not working

I am following instructions on how to set up SAML with Azure AD for HCP Azure Active Directory SSO Configuration | HashiCorp Cloud Platform
The instructions are very straightforward and easy to follow.
When I am trying to test app from the Azure AD Enterprise App page, I am getting the Hashicorp error below
Is this known issue? Has anyone managed to set up Azure AD SAML with HCP ?