You need to be a space administrator to remove or revoke space permissions.
To revoke space permissions:
To remove all permissions for a user or group, just remove the View permission. The user or group will disappear from the list when you save the permission updates. There's no need to clear all the permissions for that user or group. |
Screenshot : Assigning or Revoking Space Permissions

Space Permissions Overview
Assigning Space Permissions
Viewing Space Permissions
Users and Groups
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