adding a precision on the mapping (#5950)

* adding a precision on the mapping

* Update pages/iam/how-to/set-up-identity-federation.mdx

Co-authored-by: Rowena Jones <[email protected]>

---------

Co-authored-by: Cyril PETEL <[email protected]>
Co-authored-by: Rowena Jones <[email protected]>

Author: 3 people

pages/iam/how-to/set-up-identity-federation.mdx

@@ -36,6 +36,7 @@ Follow the steps below to set up Identity Federation for your Organization throu
    - Microsoft Entra ID (prev. Azure AD)
    - PingIdentity
    - Google Workspace
+   - Authentik
 
 ## How to set up a SAML connection
 
@@ -84,6 +85,7 @@ Once setup is complete, members can log in via SAML.
 
 <Message type="important">
   Keep in mind that:
+  - User mapping between Scaleway and the Identity Provider must be done on the user name. When testing the connection, if an error persists about the user not existing in Scaleway, make sure your Identity Provider is mapping the user on their user name
   - Members need to already have been [created manually](/iam/how-to/manage-members/#how-to-create-a-member) in Scaleway to log in.
   - If you delete a user in the IdP, the corresponding Member is not automatically deleted in your Scaleway Organization. The [deletion must happen manually](/iam/how-to/manage-members/#how-to-delete-a-member).
 </Message>