How a student account cancel stock

You won't be eligible for a refund after 5 months, on a goodwill basis, customer service may be able to cancel without an early cancellation fee.

If you are on an Enterprise account, sign out and sign in again. Instead of choosing your university, chose the individual (or private, I can't remember now the exact terminology) account. Check the plans there. 

Update this thread if this does not help.

Did you possibly subscribe under a different email address? Click on your icon at the upper right corner of the screen you linked above, and you'll see a list of all the Adobe products to which you're subscribed. If you don't see Adobe Stock there, you might have used a different email address to start a 30-day Free Trial subscription, and then didn't cancel it within the first 30 days.

The free trial converts to an annual subscription, billed monthly, if you don't cancel within 30 days. There are early termination fees associated with cancelling any Adobe annual subscription. Cancelation instructions can be found here:

https://helpx.adobe.com/stock/kb/cancel-membership-subscription-stock.htmlCancel your Stock membership

You can try to negotiate a reduction in the early termination fee. Type "Agent" in the chat box on the above page to reach a real, live person. However, given that 5 months have elapsed without you taking any action to cancel the trial, your chances of negotiating a credit seem slim...