Hi,
As Jerome pointed out, this must come from the way you configured your filter module via the Joomla modules manager.
If you have the "force redirect" setting activated there, or that you're not on a product listing page, the module will redirect to a products listing with the current menu item being the one with the id entered in the menu item setting of your module. Looking at your redirect URL, it indicates that you have 0 or nothing entered in that setting and that's why you get that URL.
So please configure your filter module properly and it should work fine.