Amend a glitch in the filters of an existing Wordpress plugin

Hi,

I have a feature called a Look-Book on a website here: https://petrarchpanels.com/look-book/

The website is in Wordpress and the Look-book feature is a plugin.

This feature allows users to select different projects and download a PDF of them all. The plugin automatically combines the project PDFs and outputs them as one single PDF.

Unfortunately there is a slight glitch on the front end when selecting 'Filters' and adding PDF selections from the 'Look-Book' menu.

I have added a video below which shows the issue.

Basically if you select one of the filters, then try adding a project to PDF, a loading icon is shown.

The only way to get rid of the loading icon is to refresh the page.

If there is someone that can iron this issue out quickly and efficiently, then please get in touch.

Any questions just ask.

Thanks.