Since the necessary steps (business profile, phone number, and verification) need to show up automatically, it appears that your embedded signup flow is lacking.
Potential causes and remedies:
- Verify App Setup: Verify that Meta Business Manager has accepted your app as a Tech Provider.
- Permissions: Verify that the scopes for WhatsApp Business Management and WhatsApp Business Messaging are appropriately set for your application.
- Embedded Signup URL: Verify that you are using the right URL and the necessary parameters.
- Changes to the Meta API: Meta might have modified the onboarding procedure. Try contacting Meta support or looking through their most recent documentation.
Try testing with a separate Meta Business Account to verify whether the problem still exists if everything is configured correctly.