php - List custom post types with custom taxonomy category assigned to them

one text

Solution:

You might need to add the relation to your args.

$args = array(
    'post_type'      => 'products',
    'posts_per_page' => -1,
    'tax_query'      => array(
        'relation' => 'AND',
        array(
            'taxonomy' => 'product_category',
            'terms'    => $category,
            'field'    => 'slug',
        ),
    ),
);

Also, check:

Is the post type spelled correctly (i.e. Are you sure it's products and not product?)
In your first query you have product_category but in your second query you have product-category. Should it be a hyphen or an underscore?
Is the value returned by $category valid?

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