Sign in to the account that owns the subscription and open Billing & usage. Select Manage payments & plan to open the Stripe billing portal, then review the subscription and follow its cancellation steps.
Check the confirmation and effective date in the portal. The current billing terms state that paid access continues to the end of the paid period; cancellation does not automatically request a refund.
If the portal is unavailable or the subscription is missing, contact support with the account email and relevant invoice date. Never send a complete card number or security code.