Brands filter doesn’t reset when deselecting the checkbox

I am very happy with what the plugin does and it works fine except for one thing:
When I select a brand, the filter does its job, but then after deselecting it, it remains active. It is the same with the button mode – brands stay selected until the “Reset filter” is pressed, no matter that the checkbox is empty (it actually is selected after refresh).
What might be the problem?

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