Second filter not filtered

When i use a group of 2 atribute filter, that is filtering “two ” atributes : merk(brand) ” & “model”.
When using the first filter it works as aspected.

But then i expect the second filter to only show the filters of the “already filtered products”, but it wont. It shows all models of all products, even after using the merk (brand filter). This way it shows irrelvant filter options.

Is that normal?

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