Pipeliner user cannot be deleted from the database. We require the account admin to send us an email in requesting Pipeliner user closure due to the extra level of security in order to prevent accidental data loss. Even though you cannot delete Pipeliner user from your database, you can deny this user access to Pipeliner i.e. he will not be able to sign in to your company Pipeliner anymore. Once you disable any Pipeliner user in admin portal, he will not be able to login to your sales pipeline again.