Parent and child brands not expanding

Hello

Thanks for your good work. I have created some brands as parents and then I have some child brands. What I need to do is that they go under eachother on the website, but the plugin shows ALL brands, regardless of being parent or child, in the same order after eachother. What is the problem and how can I fix that? I want something like this:

– Parent brand
— Child Brand
— another child brand
– Parent brand
— child brand
— another child brand
— another child brand

and so one… so that when I click on parent brand, child brands will be visible, not before.

Appreciate your help.

Regars
Edwin Dee