You have two choices for removing a user: deactivate or delete. We recommend that you deactivate users rather than deleting them.
Deactivate: This will place the user inactive without actually deleting them. This also saves all the data attributed to the user so that reports and statistics remain accurate. For standard users, this will remove them from your monthly billing.
Delete: This completely removes the user from your account. You must assign everything to an "active" user so that data will remain available and accessible in AFrame. This may have adverse effects when you want to run reports and statistics in the future. Instead, we recommend marking the user as "inactive".
You can choose either of the options under Admin > Team Members > Standard Users.
Application Link: Admin > Team Members