Filter category by manufacturer doesn't work

[sandomatyas]

A customer asked me for some help with his website.
There is a category where the name is "Shaker, flask", the slug is "shaker-flask"
The alias of the menu item is "shaker"
When I try to use the manufacturer filter above the products VM redirects to the main page of the VM
The SEF url is
/latest-products/manufacturer/biotech-usa/shaker-flask

The non-sef URL is
index.php?option=com_virtuemart&view=category&virtuemart_category_id=107&virtuemart_manufacturer_id=0&Itemid=1536&virtuemart_manufacturer_id=15

First there are two virtuemart_manufacturer_id but if I remove the first one in the router it still redirects

Could you help me how should I fix this?

[jackluter]

The problem is as the title says that I can't filter products by manufacturer in any category view.

[sandomatyas]

I had an old "Front page (deprecated)" type menu item (not the actual front page of the site). I disabled it and it solved my problem