Custom taxonomy archive template not recognised

Question

I have a custom post type, named 'products', it has a custom taxonomy that is called 'collections'.
This is how I have registered the taxonomy.

$productTaxonomyArgs = [
    'public' => true,
    'publicly_queryable' => true,
    'show_ui' => true,
    'show_in_menu' => true,
    'show_admin_column' => true,
    'description' => __('Product category', 'byronposttypes'),
    'hierarchical' => true,
    'rewrite' => [
        'slug' => __('collections', 'byronposttypes'),
        'with_front' => true,
        'hierarchical' => true,
        'ep_mask' => EP_CATEGORIES
    ],
];

register_taxonomy('collections', 'products', $productTaxonomyArgs);
register_taxonomy_for_object_type('collections', 'products');

I have created a taxonomy template by the name taxonomy-collections.php.

<?php

get_header();
$post = null;
echo '<h1>taxonomy-collections.php</h1>'; //Echo this to make sure the template works.
if (have_posts()) {
    while (have_posts()) { //rest of the code

When I navigate to /collections/lifestyle (lifestyle is one of the taxonomy terms), the <title> is 'Lifestyle Archives - [sitename]', so Wordpress does recognise the url as a taxonomy term archive. The problem is, that it doesn't even echo <h1>taxonomy-collections.php</h1> to the page. That makes me assume that the taxonomy-collections.php is not recognised by Wordpress.
Any idea as to what I am doing wrong? Thanks a lot for reading and helping!
I found out that Wordpress is falling back to index.php. But is_tax(); returns true. Not a single one of the taxonomy-specific templates seem to work (taxonomy.php, taxonomy-collection.php and taxonomy-collection-lifestyle.php), not even archive.php will work.

Answer 1

I just found out what I was doing wrong. Apparently you have to place archive pages in the root folder of your theme.
I placed them in a subfolder called templates. This works for page templates with a template name, but not for taxonomy.php, archive.php, single.php etc.

Answer 2

Try this code, its working for me ..

 function add_collection_taxonomies() {
        $productTaxonomyArgs = array(
        'public' => true,
        'publicly_queryable' => true,
        'show_ui' => true,
        'show_in_menu' => true,
        'show_admin_column' => true,
        'description' => __('Product category', 'byronposttypes'),
        'hierarchical' => true,
        'rewrite' => array(
            'slug' => __('collections', 'byronposttypes'),
            'with_front' => true,
            'hierarchical' => true,
            'ep_mask' => EP_CATEGORIES
        ),
    );
    register_taxonomy_for_object_type('collections', 'products');
    register_taxonomy('collections', 'product', $productTaxonomyArgs);