Automatically one manufacturer selected

[tomrinkes]

Dear Sirs,

In the categories, the website automatically selects 1 manufacturer and does not show products from another manufacturer. What did I do wrong and how can I put this back on all manufacturers on the category pages?

I searched the forum and the web but couldn't find anything.
Thank for any help in advanced.

Greetings,
Tom Rinkes

J4.4
VM 4.2.12

www.twr-trading.nl