How do I unhide an accordian?

First, I did not build the site but I manage/maintain the site for our business. We paid a web developer to build our site.

That said, she used this addin - Accordings by PickPlugins for some features. It works well.

For one accordian, I intended to hide one content item within the accordian if that's possible. I saw a drop-down below the last content item that said "Hide" or "Hidden" with a drop-down for Yes/No. I changed No to Yes and then clicked "Update" to save the content.

I then checked the site and now the entire accordian is missing on the site.

I went back to the settings and now the "Hide" or "Hidden" drop-down item is gone.

How do I get that drop-down back and/or how do I get the accordion to show again on the website page?

Thanks for any advice