Posts Related to Show

I’m using this plugin for a local Jazz radio station. It’s been a great solution for this site and has all the features they need.

We’re currently getting an error on the admin side when posting a blog post and trying to select from the “Related to Show” drowpdown.

When you try to select a show the error reads:
Warning: implode(): Invalid arguments passed in /home/jazz88fm/www/www/wp-content/plugins/radio-station/includes/post-types-admin.php on line 1431

I thought maybe the recent WordPress 5.6 update caused a conflict, but I rolled back to 5.4 in my staging site and still had the error.

Any help would be greatly appreciated!

The page I need help with: [log in to see the link]