If you want to stop using Kaspersky Endpoint Security Cloud and Kaspersky Security for Microsoft Office 365, you can delete your account from Kaspersky Business Hub.
When deleting an account, all data associated with that account is lost.
After you delete your account, you can no longer gain access to your workspaces in Kaspersky Endpoint Security Cloud, Kaspersky Security for Microsoft Office 365, and Kaspersky Security Center Cloud Console. If you were the only administrator in a workspace, the workspace will be duly deleted. Additionally, you lose access to your My Kaspersky account.
To delete an account in Kaspersky Business Hub:
The My Profile window of the Kaspersky Account portal opens.
Your account is deleted.