I’ve researched this issue, there are multiple suggested solutions but currently can’t find a sufficient solution that would help.

My custom post type pagination redirects to the homepage, the same solution working on by blog page.

inc/cpt.php:

register_post_type(
    'casestudies',
    array(
        'labels' => array(
            'name' => __('Case studies'),
            'singular_name' => __('Case studie')
        ),
        'public' => true,
        'has_archive' => false,
        'hierarchical' => false,
        'show_in_rest' => true, // gutenberg support
        'rewrite' => array(
            'with_front' => false,
            'slug' => 'case-studies'
        ),
        // This is where we add taxonomies to our CPT
        'taxonomies' => array( 'category' ),
        'supports' => array(
            'title',
            'thumbnail',
            'editor',
            'excerpt',
            'author'
        )
    )
);

template-casestudies.php

<div class="case-items--list grid grid-col-3 gap-48">
                    <?php $paged = (get_query_var('paged')) ? get_query_var('paged') : 1; ?>
                    <?php $args = array(
                            'posts_per_page' => 6,
                            'post_type'      => 'casestudies',
                            'category__not_in' => array(1), // 'uncateorized'
                            'paged' => $paged,
                            'orderby' => 'date',
                            'order' => 'DESC',
                        );
                        $wp_query = new WP_Query( $args );
                        while ( $wp_query->have_posts() ) : $wp_query->the_post(); ?>
                        <?php get_template_part( 'partials/card','case'); ?>
                    <?php endwhile; ?>
                </div>

                <div class="columns is-centered mt-96-desktop mt-48 mb-128-desktop mb-48">
                    <div class="column is-12 has-text-centered navigation-wrap">
                        <?php if(!is_paged()): ?><span class="prev"></span><?php endif; ?>
                        <?php echo paginate_links(array(
                            'base' => get_pagenum_link(1) . '%_%',
                            'format' => 'page/%#%',
                            'prev_text' => '<svg class="prev" xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 20 20" fill="none">
                            <path d="M8.2002 13.5999L11.8002 9.9999L8.2002 6.3999" stroke="#2756FF" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"/>
                            </svg><span>Previous</span>',
                            'next_text' => '<span>Next</span><svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 20 20" fill="none">
                            <path d="M8.2002 13.5999L11.8002 9.9999L8.2002 6.3999" stroke="#2756FF" stroke-width="1.5" stroke-linecap="round" stroke-linejoin="round"/>
                            </svg>'
                        )); ?>
                        <?php if ( $wp_query->max_num_pages == get_query_var('paged') ) : ?><span class="next"></span><?php endif; ?>
                    </div>
                </div>

I’ve tried:

• flushing permalinks
• post structure is set to /blog/%postname%/
• same code works on the blog page
• I would like to keep has_archive as false but even with archive true and archive.php as the listing still redirects to homepage

Pagination still redirects to homepage for /case-studies/page/2.

Any ideas would be welcome, thanks !

EDIT:
I also used to have a page case-studies which I deleted. It seems to be that likely some URL’s are causing this but could it be there are items in the database still after deletion and that might be causing it?

EDIT #2
If I have a template-casestudies.php with the slug /case-studie or anything else than /case-studies and has_archive => false then the pagination works. Seems like having the slug case-studies is conflicting somehow for the listing page.

If I have has_archive => true, delete the page template and just have the archive-casestudies the pagination doesnt’ work