Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hi Ohad,
You may cancel the subscription from Office 365 admin center> go to Subscription page>Billing.
More details, please refer to "Cancel your subscription" of this article.
And you can add or remove licenses at any time. You will receive a credit and prorated rebill on your next billing date after you change the number of licenses.
Please let me know if there is any misunderstanding.
Regards,
Hans