Filter names adding prefix 'Product' in the name of a filter

Hello there,
I’m probably making some rookie mistake or screwed something up alongside, but somehow I get the prefix before the name of product’s attribute, that I cannot rid off.

For example, I have attribute that is called “Ilość”, but when setting it up in the filter, I get “Product” prefix - and it’s before every attribute’s name.

I spent already many hours trying to figure it out why this is happening or just changing it somehow, but to no avail. I’m frustrated that something that simple wasting so much of my time.

I know it is a result of my lack of full knowledge of WP and probably it’s something very simple to resolve, but… I couldn’t find any viable solution