@Bence Weszely - Welcome to Microsoft Q&A and thanks for reaching out to us. It usually takes some time to reflect after the subscription is cancelled for you to delete the card.
If you don't have a Microsoft Entra account via your organization, you can cancel then delete your Azure subscriptions, and then remove your credit card from the account.
After you cancel, billing is stopped immediately. However, it can take up to 10 minutes for the cancellation to show in the portal. If you cancel in the middle of a billing period, we send the final invoice on your typical invoice date after the period ends.
Please take a look at this document for more information :https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/cancel-azure-subscription
Hope this helps. and please feel free to reach out if you have any further questions.
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