Shortcode not working

Hi,

I’m aware that the plugin says it’s not been tested on WordPress 4.1.1 but I was wondering if there might be a reason the shortcode for this plugin isn’t working?

I’ve tried the provided shortcode in the text-editor for that post:

[mgop_gallery slug="gallery-for-apartment" markup="ul"/]

I’ve then also tried it in my template:

<?php echo do_shortcode('[mgop_gallery slug="gallery-for-apartment" markup="ul"/]'); ?>

But neither seem to be working.

Are you able to help?

Thanks!

https://wordpress.org/plugins/multiple-gallery-on-post/