Popup Help

I am just starting to work with WordPress. Still trying to understand how it all works. I have done websites for many years but always the old fashion way doing the raw html or wysiwyg software. I created a popup but it seems to come and go as it pleases. Sometimes it will popup when the site is launch and then it won’t show up when you refresh the page. I would like for the popup to be displayed when the user first displays the home page or refreshes the home page. The site is http://www.shilohbiblechurchbloomsburg.org any learning would be appreciated.

Thanks Terry

https://wordpress.org/plugins/popup-maker/