Thank you for reaching out to the Community and welcome.
When you have a Student discount active, you can link your Hulu ad-supported plan from your services page.
As you mentioned the service is already active. We'd recommend deactivating the plan and activating it back again to make sure you're linking to the correct Hulu account. Then, check if your account is already linked here.
After that, you'll just need to enter the Hulu website and log in using your login credentials (email and password).
Hope this helps. If anything else comes up, don't hesitate to ask.
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