Multiple Portfolios with Toolset Types reverting to Archive File

I am using a theme called 'Reply' from You can view the demo here:

On that demo site, there is a tab called 'Work'. If you click on that tab (not a sub-menu), you will visit a portfolio page that uses a template called "Portfolio (Sortable)". The posts appear in a grid with title and featured image, and can be organised by filters at the top of the page.

I want to make multiple of these portfolio pages on my site, each with their own different posts. I contacted the Mighty Themes support and they told me to use a plugin called 'Toolset Types' to create custom post types and link them to portfolio pages.

The demo portfolio uses a post type called 'Portfolio' and I copied the settings for this post type into my own post types.
The 'Portfolio' post type (individual portfolio posts) displays on this single-portfolio.php file.
And all the 'Portfolio' posts appear on the 'Work' page, which uses this template-portfolio-sortable.php template:
The 'Portfolio' post type uses this file as its archive - archive.php file:

In Toolset Types I created my own post types with similar settings to the 'Portfolio' post type.
For the purpose of simplicity please let me focus on 'WE Musicals' which uses the slug 'west-end'.

The 'WE Musicals' post type (individual portfolio posts) displays on this single-west-end.php file.
And all the 'WE Musicals' posts appear on the 'West End' page, which uses this template-west-end-sortable.php template:
All the post types use the same archive file.

I made pages with different slugs (west-end-guide) and I set their templates to their appropriate template, such as 'West End (Sortable)'.

Therefore, with all these changes in place, I was expecting the posts to display perfectly as they had done on the demo site. However, when you visit my 'West End' portfolio page (the equivalent of 'Work' on the demo), the posts do not display correctly, as seen here:
I believe the posts themselves are showing up using the correct display format.
I was talking to a WP theme assistant and she told me that the portfolio page was rendering as an archive.

I would be very grateful for any advice as to how to solve this issue and I will happily provide further code or images. To be clear, I would like to display the 'WE Musicals' posts in the same style as the 'Work' posts on the demo site: in a grid with a featured image and title.

Thank you.