Unsure what you try to do. If users should use their Azure AD to sign in to the guest network, create a Weblogin, which has the SAML option for pre-auth.
Self-registration is for end users to generate a guest account and have it (optionally) sponsored or verified by mail/SMS.
What also may work is enable SAML for the Guest Operator Profile, and let your users create/sponsor an account by logging in to /guest/ with SAML SSO.
------------------------------
Herman Robers
------------------------
If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
In case your problem is solved, please invest the time to post a follow-up with the information on how you solved it. Others can benefit from that.
------------------------------