Cloudflare Access SAML attributes not working

I am trying to add Oracle Cloud as an SaaS app in Cloudflare access. I am using AzureAD as my IdP.

Oracle cloud requires a few extra SAML attributes. In the Access app, I added this attribute:
Name: surname
Name format: URI
IdP attribute:

When analyzing traffic using an SAML debugger, I noticed the attribute is not in the SAML request.
Any ideas?

In my configuration for the Azure AD identity provider, I’ve added family_name as an OIDC claim. I can see this value when using the test functionality in the identity provider setup page.

The problem I am facing is: how do I pass this value in the oidc claim to Access SaaS applications connected using SAML?