Pagination Not Working on `WP_Query` Archive Page

I have an archive page that pulls two different custom post types into an archive using WP_Query(). Because there is a home page to the site which shows 9 of the custom post type posts, I offset the archive page by 9 posts.

The code for this is:

However on this archive page the <?php echo paginate_links();?> function to show the pagination pages doesn’t work.

I can click through the numbers or use the next and previous arrows, but it just shows the same posts on each page.

The pagination code I’m using is:

On normal custom archive pages on the site (which don’t use WP_Query();) the pagination works fine.

Any help or assistance would be amazing.