Fix issue with custom post type query ACF, facetwp, post object.

I have a 'brand' CPT with posts.
I have a 'press ' CPT with posts using ACF fields.

I want to display 'press' posts on 'brand' archive pages that match the page. At the moment, all 'brand' pages display all the 'press' posts - I can't seem to get the query to work correctly so just relevant results display..

ie 'domain.com/brand/product1' should display all 'Press' posts that have a post object field that has 'product1' selected.

I'm using Facetwp to filter the results, which can use a custom wp query.